<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2024 Workiva-->
<!--r:2a7dc267-029f-4238-87ca-0eb79df35787,g:ee00925a-3805-4fdf-ac62-e8158bd59592-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.rgare.com/role/DocumentandEntityInformationAddress" xlink:type="simple" xlink:href="rga-20240630.xsd#DocumentandEntityInformationAddress"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DocumentandEntityInformationAddress" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_9a861538-209f-40cd-be57-d44d335e290d" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_4a3c22cf-d1be-45b9-95c8-a44733abb9b1" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_9a861538-209f-40cd-be57-d44d335e290d" xlink:to="loc_dei_DocumentInformationTable_4a3c22cf-d1be-45b9-95c8-a44733abb9b1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationDocumentAxis_c2b9c055-49f7-492a-b0ca-909ca615e03b" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationDocumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_4a3c22cf-d1be-45b9-95c8-a44733abb9b1" xlink:to="loc_dei_DocumentInformationDocumentAxis_c2b9c055-49f7-492a-b0ca-909ca615e03b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentDomain_c2b9c055-49f7-492a-b0ca-909ca615e03b_default" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_DocumentInformationDocumentAxis_c2b9c055-49f7-492a-b0ca-909ca615e03b" xlink:to="loc_dei_DocumentDomain_c2b9c055-49f7-492a-b0ca-909ca615e03b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentDomain_3263f9d5-cb6b-427e-9d74-6ddb6fa18490" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_DocumentInformationDocumentAxis_c2b9c055-49f7-492a-b0ca-909ca615e03b" xlink:to="loc_dei_DocumentDomain_3263f9d5-cb6b-427e-9d74-6ddb6fa18490" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_6d1faa50-b4ce-46a5-a839-9a3688043948" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_9a861538-209f-40cd-be57-d44d335e290d" xlink:to="loc_dei_EntityAddressAddressLine1_6d1faa50-b4ce-46a5-a839-9a3688043948" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_a04a38ac-c21b-4e57-aeea-c328b13ff31c" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_9a861538-209f-40cd-be57-d44d335e290d" xlink:to="loc_dei_EntityAddressCityOrTown_a04a38ac-c21b-4e57-aeea-c328b13ff31c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_b31d9d89-7bb8-4042-8850-f1d492f3d03e" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_9a861538-209f-40cd-be57-d44d335e290d" xlink:to="loc_dei_EntityAddressStateOrProvince_b31d9d89-7bb8-4042-8850-f1d492f3d03e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_783e61bf-c086-48a0-a742-9daded08fde4" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_9a861538-209f-40cd-be57-d44d335e290d" xlink:to="loc_dei_EntityAddressPostalZipCode_783e61bf-c086-48a0-a742-9daded08fde4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_ce764e03-5c3a-4aa2-9731-c6e351445ff5" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_9a861538-209f-40cd-be57-d44d335e290d" xlink:to="loc_dei_CityAreaCode_ce764e03-5c3a-4aa2-9731-c6e351445ff5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_2c4ade35-4f30-4a15-98e9-50afd2673bd6" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_9a861538-209f-40cd-be57-d44d335e290d" xlink:to="loc_dei_LocalPhoneNumber_2c4ade35-4f30-4a15-98e9-50afd2673bd6" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DocumentandEntityInformationDocumentandEntityInformationEntityListings" xlink:type="simple" xlink:href="rga-20240630.xsd#DocumentandEntityInformationDocumentandEntityInformationEntityListings"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DocumentandEntityInformationDocumentandEntityInformationEntityListings" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInformationLineItems_7f0e0595-54bf-45be-a285-d88a6bccf14f" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitiesTable_8dd37c1a-58ce-408f-87e6-c60305e11749" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityInformationLineItems_7f0e0595-54bf-45be-a285-d88a6bccf14f" xlink:to="loc_dei_EntitiesTable_8dd37c1a-58ce-408f-87e6-c60305e11749" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsExchangeAxis_833ac7a4-dbb8-4ffb-a92a-e97b5a268fa5" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityListingsExchangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntitiesTable_8dd37c1a-58ce-408f-87e6-c60305e11749" xlink:to="loc_dei_EntityListingsExchangeAxis_833ac7a4-dbb8-4ffb-a92a-e97b5a268fa5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_833ac7a4-dbb8-4ffb-a92a-e97b5a268fa5_default" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_EntityListingsExchangeAxis_833ac7a4-dbb8-4ffb-a92a-e97b5a268fa5" xlink:to="loc_dei_ExchangeDomain_833ac7a4-dbb8-4ffb-a92a-e97b5a268fa5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_80b33f5c-01eb-4f7c-b0b3-6bb246205a3c" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_EntityListingsExchangeAxis_833ac7a4-dbb8-4ffb-a92a-e97b5a268fa5" xlink:to="loc_dei_ExchangeDomain_80b33f5c-01eb-4f7c-b0b3-6bb246205a3c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exch_XNYS_c47c6e18-7175-40cf-9d90-f4e5f641ff56" xlink:href="https://xbrl.sec.gov/exch/2024/exch-2024.xsd#exch_XNYS"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_ExchangeDomain_80b33f5c-01eb-4f7c-b0b3-6bb246205a3c" xlink:to="loc_exch_XNYS_c47c6e18-7175-40cf-9d90-f4e5f641ff56" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_a353cac8-65c9-4fcc-a586-5f99193f5246" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntitiesTable_8dd37c1a-58ce-408f-87e6-c60305e11749" xlink:to="loc_dei_LegalEntityAxis_a353cac8-65c9-4fcc-a586-5f99193f5246" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_a353cac8-65c9-4fcc-a586-5f99193f5246_default" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_a353cac8-65c9-4fcc-a586-5f99193f5246" xlink:to="loc_dei_EntityDomain_a353cac8-65c9-4fcc-a586-5f99193f5246_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_bf8a72fb-7670-40f3-b6e5-88076cb75c69" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_a353cac8-65c9-4fcc-a586-5f99193f5246" xlink:to="loc_dei_EntityDomain_bf8a72fb-7670-40f3-b6e5-88076cb75c69" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_RGAMember_8abd4ebc-bc24-4e64-b467-c86301432718" xlink:href="rga-20240630.xsd#rga_RGAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_bf8a72fb-7670-40f3-b6e5-88076cb75c69" xlink:to="loc_rga_RGAMember_8abd4ebc-bc24-4e64-b467-c86301432718" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_RZAMember_da201801-a8e7-407f-afe8-2c99ec4ab95b" xlink:href="rga-20240630.xsd#rga_RZAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_bf8a72fb-7670-40f3-b6e5-88076cb75c69" xlink:to="loc_rga_RZAMember_da201801-a8e7-407f-afe8-2c99ec4ab95b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_RZBMember_ce2a8593-d7c7-421f-a816-d1aaf490cf89" xlink:href="rga-20240630.xsd#rga_RZBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_bf8a72fb-7670-40f3-b6e5-88076cb75c69" xlink:to="loc_rga_RZBMember_ce2a8593-d7c7-421f-a816-d1aaf490cf89" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_36266561-9515-4c65-a6c1-bf77fb57a94d" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_7f0e0595-54bf-45be-a285-d88a6bccf14f" xlink:to="loc_dei_Security12bTitle_36266561-9515-4c65-a6c1-bf77fb57a94d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_08df5ad8-fcad-40dc-853d-5e3548415d98" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_7f0e0595-54bf-45be-a285-d88a6bccf14f" xlink:to="loc_dei_TradingSymbol_08df5ad8-fcad-40dc-853d-5e3548415d98" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_03c8ceb8-4ebf-4a6b-9246-304fbe84fb21" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_7f0e0595-54bf-45be-a285-d88a6bccf14f" xlink:to="loc_dei_SecurityExchangeName_03c8ceb8-4ebf-4a6b-9246-304fbe84fb21" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETSPARENTHETICAL" xlink:type="simple" xlink:href="rga-20240630.xsd#CONDENSEDCONSOLIDATEDBALANCESHEETSPARENTHETICAL"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETSPARENTHETICAL" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_acc2dbea-bd7b-4589-b6cf-39a736d94e81" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_StatementTable_acc2dbea-bd7b-4589-b6cf-39a736d94e81" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_522c687a-d3cc-46e9-b56b-f5fb032e834a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_acc2dbea-bd7b-4589-b6cf-39a736d94e81" xlink:to="loc_srt_StatementScenarioAxis_522c687a-d3cc-46e9-b56b-f5fb032e834a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_522c687a-d3cc-46e9-b56b-f5fb032e834a_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_522c687a-d3cc-46e9-b56b-f5fb032e834a" xlink:to="loc_srt_ScenarioUnspecifiedDomain_522c687a-d3cc-46e9-b56b-f5fb032e834a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_28f47a04-0554-49ca-8aeb-28174213c301" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_522c687a-d3cc-46e9-b56b-f5fb032e834a" xlink:to="loc_srt_ScenarioUnspecifiedDomain_28f47a04-0554-49ca-8aeb-28174213c301" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_d410b7a1-a99f-456e-a541-366e897b53df" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_d410b7a1-a99f-456e-a541-366e897b53df" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_e29203da-92b5-4060-94cf-be796b4d8bd5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_e29203da-92b5-4060-94cf-be796b4d8bd5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_dce84731-4c88-45fe-9c76-4b0d586aae95" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_dce84731-4c88-45fe-9c76-4b0d586aae95" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_ef2f8d39-53d9-42b6-b125-4e5a38db08bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_ef2f8d39-53d9-42b6-b125-4e5a38db08bc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_ce674692-b769-4937-8b8e-36d7005a7e26" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_CommonStockSharesIssued_ce674692-b769-4937-8b8e-36d7005a7e26" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForLoanAndLeaseLossesRealEstate_a67a1657-6652-4da1-9092-16670fbc7e6f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllowanceForLoanAndLeaseLossesRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_AllowanceForLoanAndLeaseLossesRealEstate_a67a1657-6652-4da1-9092-16670fbc7e6f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLosses_7c779d54-d9bf-4c37-9fc2-e0d9d8b2546b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableAllowanceForCreditLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLosses_7c779d54-d9bf-4c37-9fc2-e0d9d8b2546b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_f3a71eee-1570-46d2-881a-0f149b725653" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_f3a71eee-1570-46d2-881a-0f149b725653" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateInvestmentsJointVentures_522feeca-f14f-440c-abf5-61068cf1766e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RealEstateInvestmentsJointVentures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_RealEstateInvestmentsJointVentures_522feeca-f14f-440c-abf5-61068cf1766e" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitNetAmountAtRisk_fb25ed5e-922d-486c-a291-a055e603c921" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitNetAmountAtRisk"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_MarketRiskBenefitNetAmountAtRisk_fb25ed5e-922d-486c-a291-a055e603c921" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_505825d9-1526-455e-8a05-298f5cd7c52d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_TreasuryStockCommonShares_505825d9-1526-455e-8a05-298f5cd7c52d" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsLiability_7ea2525a-bcc7-4373-91b4-c1d6f5192a14" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FundsHeldUnderReinsuranceAgreementsLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_cba3c51b-45df-4bd5-aa13-1e4251822d06" xlink:to="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsLiability_7ea2525a-bcc7-4373-91b4-c1d6f5192a14" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOME" xlink:type="simple" xlink:href="rga-20240630.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOME"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOME" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_c9720b8f-2c20-48a7-9c2f-26a4c67649c5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_73a36555-31e1-4dc0-aefc-2cdb686e2288" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_c9720b8f-2c20-48a7-9c2f-26a4c67649c5" xlink:to="loc_us-gaap_StatementTable_73a36555-31e1-4dc0-aefc-2cdb686e2288" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_74198589-c3e1-4682-a710-be862ff233d9" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_73a36555-31e1-4dc0-aefc-2cdb686e2288" xlink:to="loc_srt_StatementScenarioAxis_74198589-c3e1-4682-a710-be862ff233d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_74198589-c3e1-4682-a710-be862ff233d9_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_74198589-c3e1-4682-a710-be862ff233d9" xlink:to="loc_srt_ScenarioUnspecifiedDomain_74198589-c3e1-4682-a710-be862ff233d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_9baf9878-4a50-4e47-9e8d-4e8987815178" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_74198589-c3e1-4682-a710-be862ff233d9" xlink:to="loc_srt_ScenarioUnspecifiedDomain_9baf9878-4a50-4e47-9e8d-4e8987815178" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_733f6640-a91e-4de9-9d60-b71a0c3956bf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_c9720b8f-2c20-48a7-9c2f-26a4c67649c5" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_733f6640-a91e-4de9-9d60-b71a0c3956bf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_7c08dcde-929a-471a-84db-250520476112" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_733f6640-a91e-4de9-9d60-b71a0c3956bf" xlink:to="loc_us-gaap_ProfitLoss_7c08dcde-929a-471a-84db-250520476112" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_7ad6e2e9-bf6b-408c-a97b-9b895236daf2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_733f6640-a91e-4de9-9d60-b71a0c3956bf" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_7ad6e2e9-bf6b-408c-a97b-9b895236daf2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax_e6bb06bd-ad89-40fd-a556-0692e5e69f0d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_7ad6e2e9-bf6b-408c-a97b-9b895236daf2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax_e6bb06bd-ad89-40fd-a556-0692e5e69f0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_1d689696-9137-4b1c-b8a3-6ae961b5b8f8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_7ad6e2e9-bf6b-408c-a97b-9b895236daf2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_1d689696-9137-4b1c-b8a3-6ae961b5b8f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciLiabilityForFuturePolicyBenefitGainLossAfterReclassificationAdjustmentAndTax_96ac2aeb-89e7-4920-9621-8900e1908f10" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OciLiabilityForFuturePolicyBenefitGainLossAfterReclassificationAdjustmentAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_7ad6e2e9-bf6b-408c-a97b-9b895236daf2" xlink:to="loc_us-gaap_OciLiabilityForFuturePolicyBenefitGainLossAfterReclassificationAdjustmentAndTax_96ac2aeb-89e7-4920-9621-8900e1908f10" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciMarketRiskBenefitInstrumentSpecificCreditRiskGainLossAfterAdjustmentsAndTax_57429e91-3a80-4913-9170-7d3de98f1145" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OciMarketRiskBenefitInstrumentSpecificCreditRiskGainLossAfterAdjustmentsAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_7ad6e2e9-bf6b-408c-a97b-9b895236daf2" xlink:to="loc_us-gaap_OciMarketRiskBenefitInstrumentSpecificCreditRiskGainLossAfterAdjustmentsAndTax_57429e91-3a80-4913-9170-7d3de98f1145" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax_58e0a785-50f0-45e7-9bd8-4a3643ed5880" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_7ad6e2e9-bf6b-408c-a97b-9b895236daf2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax_58e0a785-50f0-45e7-9bd8-4a3643ed5880" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_d6bf1b0a-09d8-452e-85cf-58b715b3d80a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAbstract_7ad6e2e9-bf6b-408c-a97b-9b895236daf2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_d6bf1b0a-09d8-452e-85cf-58b715b3d80a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_8aacba90-6d73-4f53-bd54-17034e122bd9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_733f6640-a91e-4de9-9d60-b71a0c3956bf" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_8aacba90-6d73-4f53-bd54-17034e122bd9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_dfb4f010-9760-41cc-95ef-2681a871a77a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_733f6640-a91e-4de9-9d60-b71a0c3956bf" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_dfb4f010-9760-41cc-95ef-2681a871a77a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_086108db-79ed-43e5-bdb4-e111d52d5042" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAbstract_733f6640-a91e-4de9-9d60-b71a0c3956bf" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTax_086108db-79ed-43e5-bdb4-e111d52d5042" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/CondensedConsolidatedStatementsofStockholdersEquity" xlink:type="simple" xlink:href="rga-20240630.xsd#CondensedConsolidatedStatementsofStockholdersEquity"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/CondensedConsolidatedStatementsofStockholdersEquity" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_37283ef2-211e-4c6f-963d-383c1dcee99c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_StatementTable_37283ef2-211e-4c6f-963d-383c1dcee99c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementAxis_21914c29-0e23-4e9c-ac2a-380f77d766d3" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RestatementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_37283ef2-211e-4c6f-963d-383c1dcee99c" xlink:to="loc_srt_RestatementAxis_21914c29-0e23-4e9c-ac2a-380f77d766d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_21914c29-0e23-4e9c-ac2a-380f77d766d3_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RestatementAxis_21914c29-0e23-4e9c-ac2a-380f77d766d3" xlink:to="loc_srt_RestatementDomain_21914c29-0e23-4e9c-ac2a-380f77d766d3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_8e8a000d-63d4-4d3d-af80-d0234f7b3dfc" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RestatementAxis_21914c29-0e23-4e9c-ac2a-380f77d766d3" xlink:to="loc_srt_RestatementDomain_8e8a000d-63d4-4d3d-af80-d0234f7b3dfc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_13dfd9fc-b39b-4f1e-adaa-4979e09abe9b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_37283ef2-211e-4c6f-963d-383c1dcee99c" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_13dfd9fc-b39b-4f1e-adaa-4979e09abe9b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_13dfd9fc-b39b-4f1e-adaa-4979e09abe9b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_13dfd9fc-b39b-4f1e-adaa-4979e09abe9b" xlink:to="loc_us-gaap_EquityComponentDomain_13dfd9fc-b39b-4f1e-adaa-4979e09abe9b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_be5ffe9a-77e5-4df4-b1e3-b9ca718e7734" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_13dfd9fc-b39b-4f1e-adaa-4979e09abe9b" xlink:to="loc_us-gaap_EquityComponentDomain_be5ffe9a-77e5-4df4-b1e3-b9ca718e7734" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_2cbf71ad-9d50-4697-86a1-6e72d4be6323" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_be5ffe9a-77e5-4df4-b1e3-b9ca718e7734" xlink:to="loc_us-gaap_CommonStockMember_2cbf71ad-9d50-4697-86a1-6e72d4be6323" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_244dd9fd-4fdd-4226-a6f3-384ecb02d537" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_be5ffe9a-77e5-4df4-b1e3-b9ca718e7734" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_244dd9fd-4fdd-4226-a6f3-384ecb02d537" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_8c5a7099-0df7-4622-9605-b84779106964" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_be5ffe9a-77e5-4df4-b1e3-b9ca718e7734" xlink:to="loc_us-gaap_RetainedEarningsMember_8c5a7099-0df7-4622-9605-b84779106964" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_26fc67cb-15fc-4b76-beae-da0239ed2d48" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_be5ffe9a-77e5-4df4-b1e3-b9ca718e7734" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_26fc67cb-15fc-4b76-beae-da0239ed2d48" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_8867811a-b0c2-4544-9339-8547a4161802" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_be5ffe9a-77e5-4df4-b1e3-b9ca718e7734" xlink:to="loc_us-gaap_TreasuryStockCommonMember_8867811a-b0c2-4544-9339-8547a4161802" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_661d79e6-e108-4de6-9240-f83921d951d0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_StockholdersEquity_661d79e6-e108-4de6-9240-f83921d951d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_5d955834-9f93-47fc-8d64-21aefd283cc6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_NetIncomeLoss_5d955834-9f93-47fc-8d64-21aefd283cc6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_a1f3e591-1101-48ce-a733-50fce51ca58f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_a1f3e591-1101-48ce-a733-50fce51ca58f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStockCash_f8c4f277-b81d-4445-b447-9b3e55778bd3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DividendsCommonStockCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_DividendsCommonStockCash_f8c4f277-b81d-4445-b447-9b3e55778bd3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_41cee921-a591-44e6-aaed-66809951afff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_41cee921-a591-44e6-aaed-66809951afff" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued_6e431842-1b0b-419b-b508-9eda6abc4421" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued_6e431842-1b0b-419b-b508-9eda6abc4421" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_507c58ef-4bd8-4e3a-9fcc-6cd0a9ac9182" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_507c58ef-4bd8-4e3a-9fcc-6cd0a9ac9182" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterest_d75a0660-1eae-41c4-83ac-e444820a98bf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MinorityInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_MinorityInterest_d75a0660-1eae-41c4-83ac-e444820a98bf" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_3cf90c9a-42d5-4172-b95e-1481cff11529" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_3cf90c9a-42d5-4172-b95e-1481cff11529" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_165e463c-b4b8-4afa-a790-cae92fead832" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_ProfitLoss_165e463c-b4b8-4afa-a790-cae92fead832" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_6a5bd940-e9f2-4187-b437-8b8be8253778" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9f0f6499-c989-4fd6-a3ed-d2c31858e54d" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_6a5bd940-e9f2-4187-b437-8b8be8253778" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/EquityCommonStockChangesInNumberofSharesIssuedHeldInTreasuryandOutstandingDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#EquityCommonStockChangesInNumberofSharesIssuedHeldInTreasuryandOutstandingDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/EquityCommonStockChangesInNumberofSharesIssuedHeldInTreasuryandOutstandingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_02b03854-88cf-44a2-bda5-3bed56b8976d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_d3c61ef2-380b-456b-8f18-3bcc08ed6fa4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_02b03854-88cf-44a2-bda5-3bed56b8976d" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_d3c61ef2-380b-456b-8f18-3bcc08ed6fa4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_03168f21-6937-45bb-b286-cf05c1e2965b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_d3c61ef2-380b-456b-8f18-3bcc08ed6fa4" xlink:to="loc_us-gaap_StatementClassOfStockAxis_03168f21-6937-45bb-b286-cf05c1e2965b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_03168f21-6937-45bb-b286-cf05c1e2965b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_03168f21-6937-45bb-b286-cf05c1e2965b" xlink:to="loc_us-gaap_ClassOfStockDomain_03168f21-6937-45bb-b286-cf05c1e2965b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_1fa2aec9-f4b0-4943-bfea-b4a891bb79cd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_03168f21-6937-45bb-b286-cf05c1e2965b" xlink:to="loc_us-gaap_ClassOfStockDomain_1fa2aec9-f4b0-4943-bfea-b4a891bb79cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommonStockIssuableMember_cd6fe75e-aa7c-4ea3-bab0-b14d9329dc30" xlink:href="rga-20240630.xsd#rga_CommonStockIssuableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_1fa2aec9-f4b0-4943-bfea-b4a891bb79cd" xlink:to="loc_rga_CommonStockIssuableMember_cd6fe75e-aa7c-4ea3-bab0-b14d9329dc30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommonStockHeldInTreasuryMember_947d48a3-d464-464c-945c-3e3c9257da79" xlink:href="rga-20240630.xsd#rga_CommonStockHeldInTreasuryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_1fa2aec9-f4b0-4943-bfea-b4a891bb79cd" xlink:to="loc_rga_CommonStockHeldInTreasuryMember_947d48a3-d464-464c-945c-3e3c9257da79" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommonStockOutstandingMember_f805ec09-6727-4052-a150-9a7b2b521ffc" xlink:href="rga-20240630.xsd#rga_CommonStockOutstandingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_1fa2aec9-f4b0-4943-bfea-b4a891bb79cd" xlink:to="loc_rga_CommonStockOutstandingMember_f805ec09-6727-4052-a150-9a7b2b521ffc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_069ce8c3-1efc-4608-a8c1-b6ce3bce1d73" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_02b03854-88cf-44a2-bda5-3bed56b8976d" xlink:to="loc_us-gaap_CommonStockSharesIssued_069ce8c3-1efc-4608-a8c1-b6ce3bce1d73" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_0396efb4-20ac-4db4-92c2-5e69944908e6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_02b03854-88cf-44a2-bda5-3bed56b8976d" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_0396efb4-20ac-4db4-92c2-5e69944908e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_StockBasedCompensationShares_cb822367-c722-4af1-86ad-16399d58d5f3" xlink:href="rga-20240630.xsd#rga_StockBasedCompensationShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_02b03854-88cf-44a2-bda5-3bed56b8976d" xlink:to="loc_rga_StockBasedCompensationShares_cb822367-c722-4af1-86ad-16399d58d5f3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_f06b359b-e21e-402d-a9d5-b360d51c834e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonStockSharesIssued"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/EquityBalanceofandChangesinEachComponentofAOCIDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#EquityBalanceofandChangesinEachComponentofAOCIDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/EquityBalanceofandChangesinEachComponentofAOCIDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_9ab1e215-2ace-4a39-a456-e3ca2091e27a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_b5d3759d-e783-4762-b200-5cd0c44bc87f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_9ab1e215-2ace-4a39-a456-e3ca2091e27a" xlink:to="loc_us-gaap_StatementTable_b5d3759d-e783-4762-b200-5cd0c44bc87f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_a77891a8-fcfa-40c6-b9a8-a82fffe44595" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_b5d3759d-e783-4762-b200-5cd0c44bc87f" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_a77891a8-fcfa-40c6-b9a8-a82fffe44595" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_a77891a8-fcfa-40c6-b9a8-a82fffe44595_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_a77891a8-fcfa-40c6-b9a8-a82fffe44595" xlink:to="loc_us-gaap_EquityComponentDomain_a77891a8-fcfa-40c6-b9a8-a82fffe44595_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_ea53a8d6-0567-4f5d-b984-e247627399d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_a77891a8-fcfa-40c6-b9a8-a82fffe44595" xlink:to="loc_us-gaap_EquityComponentDomain_ea53a8d6-0567-4f5d-b984-e247627399d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_f91caf8d-b744-4940-a415-5638ecde8a35" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_ea53a8d6-0567-4f5d-b984-e247627399d1" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_f91caf8d-b744-4940-a415-5638ecde8a35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_00affdb5-d1b3-43f4-8413-39a607321517" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_ea53a8d6-0567-4f5d-b984-e247627399d1" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_00affdb5-d1b3-43f4-8413-39a607321517" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_10f67d14-a08b-485e-a2d1-d4fae3b3b136" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_ea53a8d6-0567-4f5d-b984-e247627399d1" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_10f67d14-a08b-485e-a2d1-d4fae3b3b136" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociMarketRiskBenefitInstrumentSpecificCreditRiskParentMember_da6a30e6-1b82-425c-8c0a-ef7c6429f43a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AociMarketRiskBenefitInstrumentSpecificCreditRiskParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_ea53a8d6-0567-4f5d-b984-e247627399d1" xlink:to="loc_us-gaap_AociMarketRiskBenefitInstrumentSpecificCreditRiskParentMember_da6a30e6-1b82-425c-8c0a-ef7c6429f43a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociLiabilityForFuturePolicyBenefitParentMember_975f2041-c578-41e1-b6ed-364d74480cd1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AociLiabilityForFuturePolicyBenefitParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_ea53a8d6-0567-4f5d-b984-e247627399d1" xlink:to="loc_us-gaap_AociLiabilityForFuturePolicyBenefitParentMember_975f2041-c578-41e1-b6ed-364d74480cd1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_03cc61d6-10dc-460c-b860-b657e7a372c4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9ab1e215-2ace-4a39-a456-e3ca2091e27a" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_03cc61d6-10dc-460c-b860-b657e7a372c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_65bd26e6-c90d-4f8e-bb45-d4bd2c86d1d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9ab1e215-2ace-4a39-a456-e3ca2091e27a" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_65bd26e6-c90d-4f8e-bb45-d4bd2c86d1d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_c5815694-a215-4ca1-bdf6-4b10eb0cb078" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9ab1e215-2ace-4a39-a456-e3ca2091e27a" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_c5815694-a215-4ca1-bdf6-4b10eb0cb078" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTax_9e44665e-5b19-4529-9253-9fc251ca78a8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9ab1e215-2ace-4a39-a456-e3ca2091e27a" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossTax_9e44665e-5b19-4529-9253-9fc251ca78a8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_c1ed0c61-325d-4813-8c11-582494811af2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/EquityBalanceofandChangesinEachComponentofAOCIFootnoteDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#EquityBalanceofandChangesinEachComponentofAOCIFootnoteDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/EquityBalanceofandChangesinEachComponentofAOCIFootnoteDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_ffd36d46-442b-4184-8e1f-f9dfd209ad18" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_5535c6d7-c749-4ed9-b8c8-2cd14a3505ea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_ffd36d46-442b-4184-8e1f-f9dfd209ad18" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_5535c6d7-c749-4ed9-b8c8-2cd14a3505ea" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_41a9918e-7076-47e3-8c8e-5f88b6556044" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_5535c6d7-c749-4ed9-b8c8-2cd14a3505ea" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_41a9918e-7076-47e3-8c8e-5f88b6556044" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_41a9918e-7076-47e3-8c8e-5f88b6556044_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_41a9918e-7076-47e3-8c8e-5f88b6556044" xlink:to="loc_us-gaap_HedgingRelationshipDomain_41a9918e-7076-47e3-8c8e-5f88b6556044_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_cd507bf5-e2b7-4587-a1b7-4117ea680dac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_41a9918e-7076-47e3-8c8e-5f88b6556044" xlink:to="loc_us-gaap_HedgingRelationshipDomain_cd507bf5-e2b7-4587-a1b7-4117ea680dac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_d2a4efa0-3fa0-46f9-ba21-8c4f6494b7a8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_cd507bf5-e2b7-4587-a1b7-4117ea680dac" xlink:to="loc_us-gaap_CashFlowHedgingMember_d2a4efa0-3fa0-46f9-ba21-8c4f6494b7a8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_776bce11-ad28-4eae-ab5c-5576d3a8143a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_ffd36d46-442b-4184-8e1f-f9dfd209ad18" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_776bce11-ad28-4eae-ab5c-5576d3a8143a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/EquityScheduleofReclassificationsoutofAOCIDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#EquityScheduleofReclassificationsoutofAOCIDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/EquityScheduleofReclassificationsoutofAOCIDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AociReclassificationTable_69b8e025-1827-440b-9b2b-d1062c9d8cda" xlink:href="rga-20240630.xsd#rga_AociReclassificationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:to="loc_rga_AociReclassificationTable_69b8e025-1827-440b-9b2b-d1062c9d8cda" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_06a9208b-520f-41ce-bc8d-fd98efcf2b63" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_AociReclassificationTable_69b8e025-1827-440b-9b2b-d1062c9d8cda" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_06a9208b-520f-41ce-bc8d-fd98efcf2b63" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_06a9208b-520f-41ce-bc8d-fd98efcf2b63_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_06a9208b-520f-41ce-bc8d-fd98efcf2b63" xlink:to="loc_us-gaap_HedgingRelationshipDomain_06a9208b-520f-41ce-bc8d-fd98efcf2b63_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_e0a1b78b-6193-4a86-8a5f-69b9cd49b18e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_06a9208b-520f-41ce-bc8d-fd98efcf2b63" xlink:to="loc_us-gaap_HedgingRelationshipDomain_e0a1b78b-6193-4a86-8a5f-69b9cd49b18e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrencySwapMember_88074495-b1d8-40b9-99f8-da5069a21325" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CurrencySwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_e0a1b78b-6193-4a86-8a5f-69b9cd49b18e" xlink:to="loc_us-gaap_CurrencySwapMember_88074495-b1d8-40b9-99f8-da5069a21325" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_InterestRateOptionsMember_b356c7b0-a897-4431-b296-f4069b3790cc" xlink:href="rga-20240630.xsd#rga_InterestRateOptionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_e0a1b78b-6193-4a86-8a5f-69b9cd49b18e" xlink:to="loc_rga_InterestRateOptionsMember_b356c7b0-a897-4431-b296-f4069b3790cc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AociComponentsAxis_bf7c743a-0218-44ea-9223-854841a66324" xlink:href="rga-20240630.xsd#rga_AociComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_AociReclassificationTable_69b8e025-1827-440b-9b2b-d1062c9d8cda" xlink:to="loc_rga_AociComponentsAxis_bf7c743a-0218-44ea-9223-854841a66324" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AociComponentsDomain_bf7c743a-0218-44ea-9223-854841a66324_default" xlink:href="rga-20240630.xsd#rga_AociComponentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_AociComponentsAxis_bf7c743a-0218-44ea-9223-854841a66324" xlink:to="loc_rga_AociComponentsDomain_bf7c743a-0218-44ea-9223-854841a66324_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AociComponentsDomain_e60bbdc2-0681-4dcd-a5af-737547e350c8" xlink:href="rga-20240630.xsd#rga_AociComponentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_AociComponentsAxis_bf7c743a-0218-44ea-9223-854841a66324" xlink:to="loc_rga_AociComponentsDomain_e60bbdc2-0681-4dcd-a5af-737547e350c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_UnrealizedAppreciationDepreciationOfInvestmentsMember_9923462d-d6e6-4dcf-9e5d-6a6787d9022e" xlink:href="rga-20240630.xsd#rga_UnrealizedAppreciationDepreciationOfInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AociComponentsDomain_e60bbdc2-0681-4dcd-a5af-737547e350c8" xlink:to="loc_rga_UnrealizedAppreciationDepreciationOfInvestmentsMember_9923462d-d6e6-4dcf-9e5d-6a6787d9022e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AmortizationOfUnrealizedPensionAndPostretirementBenefitsMember_a518b584-dfec-4825-8a47-03b18d2605f6" xlink:href="rga-20240630.xsd#rga_AmortizationOfUnrealizedPensionAndPostretirementBenefitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AociComponentsDomain_e60bbdc2-0681-4dcd-a5af-737547e350c8" xlink:to="loc_rga_AmortizationOfUnrealizedPensionAndPostretirementBenefitsMember_a518b584-dfec-4825-8a47-03b18d2605f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AmountsReclassifiedFromAociMember_c752de08-ce58-4b10-9215-797b2347d325" xlink:href="rga-20240630.xsd#rga_AmountsReclassifiedFromAociMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AociComponentsDomain_e60bbdc2-0681-4dcd-a5af-737547e350c8" xlink:to="loc_rga_AmountsReclassifiedFromAociMember_c752de08-ce58-4b10-9215-797b2347d325" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_UnrealizedGainLossReclassAxis_d2762e51-86d3-4f55-b1ca-00f5dda2bd36" xlink:href="rga-20240630.xsd#rga_UnrealizedGainLossReclassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_AociReclassificationTable_69b8e025-1827-440b-9b2b-d1062c9d8cda" xlink:to="loc_rga_UnrealizedGainLossReclassAxis_d2762e51-86d3-4f55-b1ca-00f5dda2bd36" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_UnrealizedGainLossReclassDomain_d2762e51-86d3-4f55-b1ca-00f5dda2bd36_default" xlink:href="rga-20240630.xsd#rga_UnrealizedGainLossReclassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_UnrealizedGainLossReclassAxis_d2762e51-86d3-4f55-b1ca-00f5dda2bd36" xlink:to="loc_rga_UnrealizedGainLossReclassDomain_d2762e51-86d3-4f55-b1ca-00f5dda2bd36_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_UnrealizedGainLossReclassDomain_d884de6f-0460-4519-81b9-5a201c8f1299" xlink:href="rga-20240630.xsd#rga_UnrealizedGainLossReclassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_UnrealizedGainLossReclassAxis_d2762e51-86d3-4f55-b1ca-00f5dda2bd36" xlink:to="loc_rga_UnrealizedGainLossReclassDomain_d884de6f-0460-4519-81b9-5a201c8f1299" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_UnrealizedGainsLossesOnAvailableForSaleSecuritiesMember_27f52735-b2ad-4b75-9dd4-21708ffdb6f4" xlink:href="rga-20240630.xsd#rga_UnrealizedGainsLossesOnAvailableForSaleSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_UnrealizedGainLossReclassDomain_d884de6f-0460-4519-81b9-5a201c8f1299" xlink:to="loc_rga_UnrealizedGainsLossesOnAvailableForSaleSecuritiesMember_27f52735-b2ad-4b75-9dd4-21708ffdb6f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfOtherInvestments_978d34cd-d040-4aee-a53d-b7db5e38909c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnSaleOfOtherInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:to="loc_us-gaap_GainLossOnSaleOfOtherInvestments_978d34cd-d040-4aee-a53d-b7db5e38909c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_9f89f2b2-89a3-4121-aed2-19d59fbbc9d7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_9f89f2b2-89a3-4121-aed2-19d59fbbc9d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_251224b5-0f07-4fda-8255-da72d3422728" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_251224b5-0f07-4fda-8255-da72d3422728" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_84093dd6-17d2-4c02-9526-39ef68e72426" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_84093dd6-17d2-4c02-9526-39ef68e72426" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_ed351d91-5d4a-4586-bfa3-ee30b98df060" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_ed351d91-5d4a-4586-bfa3-ee30b98df060" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_6d4156bf-9e8e-4b0c-ae9a-dcdf238efe11" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_6d4156bf-9e8e-4b0c-ae9a-dcdf238efe11" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_0c7b0b4d-a9ac-46f8-8571-92be0d604419" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_a071eba5-6a83-48fd-b780-5d6ef37e5457" xlink:to="loc_us-gaap_NetIncomeLoss_0c7b0b4d-a9ac-46f8-8571-92be0d604419" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/EquityNarrativeDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#EquityNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/EquityNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityClassOfTreasuryStockLineItems_869a6a96-3c2c-4b08-b8f6-1b23fc1dc31b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityClassOfTreasuryStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfTreasuryStockTable_4a2822b2-1e0c-410c-8b2d-eb8642849ca3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfTreasuryStockTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_869a6a96-3c2c-4b08-b8f6-1b23fc1dc31b" xlink:to="loc_us-gaap_ClassOfTreasuryStockTable_4a2822b2-1e0c-410c-8b2d-eb8642849ca3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_70c3f5d1-9e2a-4c01-a1b5-21e2df52b43b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_4a2822b2-1e0c-410c-8b2d-eb8642849ca3" xlink:to="loc_us-gaap_StatementClassOfStockAxis_70c3f5d1-9e2a-4c01-a1b5-21e2df52b43b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_70c3f5d1-9e2a-4c01-a1b5-21e2df52b43b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_70c3f5d1-9e2a-4c01-a1b5-21e2df52b43b" xlink:to="loc_us-gaap_ClassOfStockDomain_70c3f5d1-9e2a-4c01-a1b5-21e2df52b43b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_c6019888-9927-4726-afc6-a66a4e35de7c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_70c3f5d1-9e2a-4c01-a1b5-21e2df52b43b" xlink:to="loc_us-gaap_ClassOfStockDomain_c6019888-9927-4726-afc6-a66a4e35de7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommonStockHeldInTreasuryMember_0c2b3b3c-a939-4ba2-be50-e4496e49430e" xlink:href="rga-20240630.xsd#rga_CommonStockHeldInTreasuryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_c6019888-9927-4726-afc6-a66a4e35de7c" xlink:to="loc_rga_CommonStockHeldInTreasuryMember_0c2b3b3c-a939-4ba2-be50-e4496e49430e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_49697cc6-d4a8-45d5-a1cd-59fef5524d61" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_4a2822b2-1e0c-410c-8b2d-eb8642849ca3" xlink:to="loc_srt_ShareRepurchaseProgramAxis_49697cc6-d4a8-45d5-a1cd-59fef5524d61" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_49697cc6-d4a8-45d5-a1cd-59fef5524d61_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_49697cc6-d4a8-45d5-a1cd-59fef5524d61" xlink:to="loc_srt_ShareRepurchaseProgramDomain_49697cc6-d4a8-45d5-a1cd-59fef5524d61_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_22bb709c-e55b-4ec9-8d0c-196a5376ae92" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_49697cc6-d4a8-45d5-a1cd-59fef5524d61" xlink:to="loc_srt_ShareRepurchaseProgramDomain_22bb709c-e55b-4ec9-8d0c-196a5376ae92" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ShareRepurchaseProgramMember_b9b132a2-0f4a-4ee7-b84d-9143d32140a5" xlink:href="rga-20240630.xsd#rga_ShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_22bb709c-e55b-4ec9-8d0c-196a5376ae92" xlink:to="loc_rga_ShareRepurchaseProgramMember_b9b132a2-0f4a-4ee7-b84d-9143d32140a5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_23a19110-40b1-429f-b02d-a03bc957cab3" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_869a6a96-3c2c-4b08-b8f6-1b23fc1dc31b" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_23a19110-40b1-429f-b02d-a03bc957cab3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterest_39ba07bf-1de9-4c1b-97f3-1e5a144a2655" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MinorityInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_869a6a96-3c2c-4b08-b8f6-1b23fc1dc31b" xlink:to="loc_us-gaap_MinorityInterest_39ba07bf-1de9-4c1b-97f3-1e5a144a2655" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_6dc5eb93-7908-4c43-8fe8-cd28abc14fa3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_869a6a96-3c2c-4b08-b8f6-1b23fc1dc31b" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_6dc5eb93-7908-4c43-8fe8-cd28abc14fa3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_f0bacc3c-e1bc-4a73-8350-145a620c421c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_869a6a96-3c2c-4b08-b8f6-1b23fc1dc31b" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_f0bacc3c-e1bc-4a73-8350-145a620c421c" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/EquityBasedCompensationNarrativeDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#EquityBasedCompensationNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/EquityBasedCompensationNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_39e6dc2a-2aee-4557-a7ba-743579399b59" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_39e6dc2a-2aee-4557-a7ba-743579399b59" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_76bedeaa-f060-4ecf-bbc3-102827da9dac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_39e6dc2a-2aee-4557-a7ba-743579399b59" xlink:to="loc_us-gaap_AwardTypeAxis_76bedeaa-f060-4ecf-bbc3-102827da9dac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_76bedeaa-f060-4ecf-bbc3-102827da9dac_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_76bedeaa-f060-4ecf-bbc3-102827da9dac" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_76bedeaa-f060-4ecf-bbc3-102827da9dac_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_cbd0d84d-deab-4e8f-a84f-afc980b88cf3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_76bedeaa-f060-4ecf-bbc3-102827da9dac" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_cbd0d84d-deab-4e8f-a84f-afc980b88cf3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_8b788a6a-6202-4977-8a7c-58df117f0d39" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_cbd0d84d-deab-4e8f-a84f-afc980b88cf3" xlink:to="loc_us-gaap_PerformanceSharesMember_8b788a6a-6202-4977-8a7c-58df117f0d39" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_36011aff-bad1-4f7d-8021-b7318aa4edcd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_cbd0d84d-deab-4e8f-a84f-afc980b88cf3" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_36011aff-bad1-4f7d-8021-b7318aa4edcd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_23a612a3-15fc-45ed-b169-03aa50700661" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_23a612a3-15fc-45ed-b169-03aa50700661" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_bfdf9a52-4c87-40b9-b467-1c37484f1597" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_bfdf9a52-4c87-40b9-b467-1c37484f1597" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_8bac5196-37ed-42b4-aed7-885b1be5107a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_8bac5196-37ed-42b4-aed7-885b1be5107a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_574e2bc8-38ca-4311-b0d7-5a042f7cd77c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_574e2bc8-38ca-4311-b0d7-5a042f7cd77c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_734c88d8-99ee-487a-91fa-c74d2652ec0f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_734c88d8-99ee-487a-91fa-c74d2652ec0f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_cf3231d6-56ff-4a43-9d90-d60566d58391" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_cf3231d6-56ff-4a43-9d90-d60566d58391" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_74b700e4-5479-4652-966b-30755f73ec84" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_74b700e4-5479-4652-966b-30755f73ec84" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_9cae6b8d-f52c-4129-88dd-1fc1acacc8d3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c21c0219-3f12-44a8-851c-42dacc4eba5f" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_9cae6b8d-f52c-4129-88dd-1fc1acacc8d3" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FuturePolicyBenefitsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FuturePolicyBenefitsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FuturePolicyBenefitsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_b8bdeb84-6dcd-4b39-89e6-c7c1271a4719" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_b8bdeb84-6dcd-4b39-89e6-c7c1271a4719" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_cbde67be-22bf-43e1-b111-75e8cd298a2f" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_b8bdeb84-6dcd-4b39-89e6-c7c1271a4719" xlink:to="loc_srt_ProductOrServiceAxis_cbde67be-22bf-43e1-b111-75e8cd298a2f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_cbde67be-22bf-43e1-b111-75e8cd298a2f_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_cbde67be-22bf-43e1-b111-75e8cd298a2f" xlink:to="loc_srt_ProductsAndServicesDomain_cbde67be-22bf-43e1-b111-75e8cd298a2f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_030b286f-c454-4ae3-aa57-6d2b364ac730" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_cbde67be-22bf-43e1-b111-75e8cd298a2f" xlink:to="loc_srt_ProductsAndServicesDomain_030b286f-c454-4ae3-aa57-6d2b364ac730" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_bd54b5f3-52e1-4edc-a7aa-b46040975074" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_030b286f-c454-4ae3-aa57-6d2b364ac730" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_bd54b5f3-52e1-4edc-a7aa-b46040975074" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_daa857ea-58d4-428b-8c21-5e8887e2f1ce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_030b286f-c454-4ae3-aa57-6d2b364ac730" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_daa857ea-58d4-428b-8c21-5e8887e2f1ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_ab2eb90d-0d5b-42cd-b5a3-22cd604a1077" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_b8bdeb84-6dcd-4b39-89e6-c7c1271a4719" xlink:to="loc_srt_StatementGeographicalAxis_ab2eb90d-0d5b-42cd-b5a3-22cd604a1077" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_ab2eb90d-0d5b-42cd-b5a3-22cd604a1077_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_ab2eb90d-0d5b-42cd-b5a3-22cd604a1077" xlink:to="loc_srt_SegmentGeographicalDomain_ab2eb90d-0d5b-42cd-b5a3-22cd604a1077_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_e4b26039-f598-4351-a44c-3f815cf319c5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_ab2eb90d-0d5b-42cd-b5a3-22cd604a1077" xlink:to="loc_srt_SegmentGeographicalDomain_e4b26039-f598-4351-a44c-3f815cf319c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_a63e1e11-b88d-4cef-a0ac-e48c74759b01" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_e4b26039-f598-4351-a44c-3f815cf319c5" xlink:to="loc_srt_AmericasMember_a63e1e11-b88d-4cef-a0ac-e48c74759b01" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_f7b6b867-ba46-4afb-b9b8-4c2515c2a34d" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_e4b26039-f598-4351-a44c-3f815cf319c5" xlink:to="loc_country_CA_f7b6b867-ba46-4afb-b9b8-4c2515c2a34d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_822ca6b4-cac0-424a-9066-a69d03ac051f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_e4b26039-f598-4351-a44c-3f815cf319c5" xlink:to="loc_us-gaap_EMEAMember_822ca6b4-cac0-424a-9066-a69d03ac051f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_65fa23b1-e0ad-465f-919f-f088680e8975" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_e4b26039-f598-4351-a44c-3f815cf319c5" xlink:to="loc_srt_AsiaPacificMember_65fa23b1-e0ad-465f-919f-f088680e8975" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_491fe77e-afec-4fdb-997f-f1e851479e1b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_b8bdeb84-6dcd-4b39-89e6-c7c1271a4719" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_491fe77e-afec-4fdb-997f-f1e851479e1b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_491fe77e-afec-4fdb-997f-f1e851479e1b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_491fe77e-afec-4fdb-997f-f1e851479e1b" xlink:to="loc_us-gaap_SegmentDomain_491fe77e-afec-4fdb-997f-f1e851479e1b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_c5cd1d89-cf0d-4316-a265-73adfad6ebc4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_491fe77e-afec-4fdb-997f-f1e851479e1b" xlink:to="loc_us-gaap_SegmentDomain_c5cd1d89-cf0d-4316-a265-73adfad6ebc4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_c05f91a7-35d4-49f3-8939-2a5fa603dcc7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_c5cd1d89-cf0d-4316-a265-73adfad6ebc4" xlink:to="loc_us-gaap_AllOtherSegmentsMember_c05f91a7-35d4-49f3-8939-2a5fa603dcc7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociLiabilityForFuturePolicyBenefitExpectedNetPremiumBeforeTax_2358cf82-6b09-47c3-ad04-f73759f43770" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AociLiabilityForFuturePolicyBenefitExpectedNetPremiumBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_AociLiabilityForFuturePolicyBenefitExpectedNetPremiumBeforeTax_2358cf82-6b09-47c3-ad04-f73759f43770" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumCumulativeIncreaseDecreaseFromCashFlowChange_a7f67f51-71e8-4fd4-8fa4-5ed2cb4cde88" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumCumulativeIncreaseDecreaseFromCashFlowChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumCumulativeIncreaseDecreaseFromCashFlowChange_a7f67f51-71e8-4fd4-8fa4-5ed2cb4cde88" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumCumulativeIncreaseDecreaseOfActualVarianceFromExpectedExperience_20b5de3c-0ad0-4871-8d3b-c8f22f125d82" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumCumulativeIncreaseDecreaseOfActualVarianceFromExpectedExperience"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumCumulativeIncreaseDecreaseOfActualVarianceFromExpectedExperience_20b5de3c-0ad0-4871-8d3b-c8f22f125d82" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumOriginalDiscountRateBeforeReinsuranceAfterCashFlowChange_061c561a-9260-4286-bc18-23a585989caf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumOriginalDiscountRateBeforeReinsuranceAfterCashFlowChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumOriginalDiscountRateBeforeReinsuranceAfterCashFlowChange_061c561a-9260-4286-bc18-23a585989caf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumIssuance_7f3fc34f-779d-4536-b95c-6e6a461fa0e3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumIssuance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumIssuance_7f3fc34f-779d-4536-b95c-6e6a461fa0e3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumInterestIncome_a59835ae-e0b5-4bb5-8538-7fe3313fedf7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumInterestIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumInterestIncome_a59835ae-e0b5-4bb5-8538-7fe3313fedf7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumNetPremiumCollected_7ecdd317-e235-449a-af31-89f8902a5ff3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumNetPremiumCollected"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumNetPremiumCollected_7ecdd317-e235-449a-af31-89f8902a5ff3" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumDerecognition_4edcb009-500f-46ae-8752-3ba39aa745c1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumDerecognition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumDerecognition_4edcb009-500f-46ae-8752-3ba39aa745c1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumIncreaseDecreaseForOtherChange_9a4cb72b-b663-455e-a30c-e5bd8d03abc3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumIncreaseDecreaseForOtherChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumIncreaseDecreaseForOtherChange_9a4cb72b-b663-455e-a30c-e5bd8d03abc3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumBeforeReinsuranceAfterDiscountRateChange_d0b51d67-2268-44f1-a877-1fe32c0ff0f3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumBeforeReinsuranceAfterDiscountRateChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedNetPremiumBeforeReinsuranceAfterDiscountRateChange_d0b51d67-2268-44f1-a877-1fe32c0ff0f3" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociLiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitBeforeTax_aa8a81f2-2662-45cf-8943-2d481455ccd6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AociLiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_AociLiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitBeforeTax_aa8a81f2-2662-45cf-8943-2d481455ccd6" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitCumulativeIncreaseDecreaseFromCashFlowChange_b10b4875-6df4-48f4-9f17-78349c381eed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitCumulativeIncreaseDecreaseFromCashFlowChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitCumulativeIncreaseDecreaseFromCashFlowChange_b10b4875-6df4-48f4-9f17-78349c381eed" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitCumulativeIncreaseDecreaseOfActualVarianceFromExpectedExperience_9eaebbc6-abd1-4d48-8a34-d8c195eb5fe3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitCumulativeIncreaseDecreaseOfActualVarianceFromExpectedExperience"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitCumulativeIncreaseDecreaseOfActualVarianceFromExpectedExperience_9eaebbc6-abd1-4d48-8a34-d8c195eb5fe3" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureBenefitOriginalDiscountRateBeforeReinsuranceAfterCashFlowChange_8bc95eca-f2c6-4747-a6ff-5ed2480e3095" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureBenefitOriginalDiscountRateBeforeReinsuranceAfterCashFlowChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureBenefitOriginalDiscountRateBeforeReinsuranceAfterCashFlowChange_8bc95eca-f2c6-4747-a6ff-5ed2480e3095" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitIssuance_30c8ae8e-e98f-4b2b-bff3-b1addb5642e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitIssuance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitIssuance_30c8ae8e-e98f-4b2b-bff3-b1addb5642e2" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitInterestExpense_22716118-d83e-4d21-bbba-69480311b3fd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitInterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitInterestExpense_22716118-d83e-4d21-bbba-69480311b3fd" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitsPaymentForBenefits_2bd4b335-61d6-4a39-a12c-1c5fb7ada409" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitsPaymentForBenefits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitsPaymentForBenefits_2bd4b335-61d6-4a39-a12c-1c5fb7ada409" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitDerecognition_177ec871-67f2-4d78-9e1c-6546594d03f0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitDerecognition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitDerecognition_177ec871-67f2-4d78-9e1c-6546594d03f0" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitIncreaseDecreaseForOtherChange_caacf52a-5847-463a-8791-7b3c0616f520" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitIncreaseDecreaseForOtherChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitIncreaseDecreaseForOtherChange_caacf52a-5847-463a-8791-7b3c0616f520" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitBeforeReinsuranceAfterDiscountRateChange_796ebfc8-4676-4d47-a283-df0f213d9d8d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitBeforeReinsuranceAfterDiscountRateChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitBeforeReinsuranceAfterDiscountRateChange_796ebfc8-4676-4d47-a283-df0f213d9d8d" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_LiabilityForFuturePolicyBenefitsCumulativeAmountOfFairValueHedgingAdjustments_6a30a4b9-3dfb-42ed-ad69-a22c236d7b96" xlink:href="rga-20240630.xsd#rga_LiabilityForFuturePolicyBenefitsCumulativeAmountOfFairValueHedgingAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_rga_LiabilityForFuturePolicyBenefitsCumulativeAmountOfFairValueHedgingAdjustments_6a30a4b9-3dfb-42ed-ad69-a22c236d7b96" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefits_16183c97-7c8f-43b5-8dbe-f42d418331cf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefits_16183c97-7c8f-43b5-8dbe-f42d418331cf" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitReinsuranceRecoverableAfterAllowance_67a42dc1-a1b3-463f-b507-629c800634db" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitReinsuranceRecoverableAfterAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitReinsuranceRecoverableAfterAllowance_67a42dc1-a1b3-463f-b507-629c800634db" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitAfterReinsurance_32f123b2-a5cc-43d0-a0b0-896beb021377" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitAfterReinsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitAfterReinsurance_32f123b2-a5cc-43d0-a0b0-896beb021377" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitWeightedAverageDuration_38c22838-68b0-4602-b799-5f682348aac1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitWeightedAverageDuration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitWeightedAverageDuration_38c22838-68b0-4602-b799-5f682348aac1" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitWeightedAverageInterestAccretionRate_9df15900-cd17-4ddb-a9cf-e759da845bee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitWeightedAverageInterestAccretionRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitWeightedAverageInterestAccretionRate_9df15900-cd17-4ddb-a9cf-e759da845bee" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitCurrentWeightedAverageDiscountRate_10e63eca-1f09-4f34-94ed-de6caed256ac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitCurrentWeightedAverageDiscountRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitCurrentWeightedAverageDiscountRate_10e63eca-1f09-4f34-94ed-de6caed256ac" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense_2be12b55-9548-4970-8564-78ce8b19738f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense_2be12b55-9548-4970-8564-78ce8b19738f" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FuturePolicyBenefitsUnearnedRevenueLiability_12d20f90-9458-4545-86bc-100546214c87" xlink:href="rga-20240630.xsd#rga_FuturePolicyBenefitsUnearnedRevenueLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_rga_FuturePolicyBenefitsUnearnedRevenueLiability_12d20f90-9458-4545-86bc-100546214c87" xlink:type="arc" order="28"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalLiabilityLongDurationInsuranceBeforeReinsuranceAfterDiscountRateChange_99b237b8-12cd-4d8a-b754-c2374c6cbb7a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdditionalLiabilityLongDurationInsuranceBeforeReinsuranceAfterDiscountRateChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_9c6f17cf-48c6-4243-8770-429dd1af02ba" xlink:to="loc_us-gaap_AdditionalLiabilityLongDurationInsuranceBeforeReinsuranceAfterDiscountRateChange_99b237b8-12cd-4d8a-b754-c2374c6cbb7a" xlink:type="arc" order="29"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FuturePolicyBenefitsUndiscountedandDiscountedDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FuturePolicyBenefitsUndiscountedandDiscountedDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FuturePolicyBenefitsUndiscountedandDiscountedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_4bd6fe2b-2acf-49cc-8f41-56c16a698911" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_1713b632-4110-472d-b869-a678144453df" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitActivityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_4bd6fe2b-2acf-49cc-8f41-56c16a698911" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_1713b632-4110-472d-b869-a678144453df" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_fff44606-b423-4ae0-bb06-912d21c3c952" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_1713b632-4110-472d-b869-a678144453df" xlink:to="loc_srt_MajorCustomersAxis_fff44606-b423-4ae0-bb06-912d21c3c952" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_fff44606-b423-4ae0-bb06-912d21c3c952_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_fff44606-b423-4ae0-bb06-912d21c3c952" xlink:to="loc_srt_NameOfMajorCustomerDomain_fff44606-b423-4ae0-bb06-912d21c3c952_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_763504b2-0e6a-42d5-aecf-8c7661baeb60" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_fff44606-b423-4ae0-bb06-912d21c3c952" xlink:to="loc_srt_NameOfMajorCustomerDomain_763504b2-0e6a-42d5-aecf-8c7661baeb60" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_499c4c51-c2c9-451b-a594-4dbdff7f591d" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_1713b632-4110-472d-b869-a678144453df" xlink:to="loc_srt_StatementGeographicalAxis_499c4c51-c2c9-451b-a594-4dbdff7f591d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_499c4c51-c2c9-451b-a594-4dbdff7f591d_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_499c4c51-c2c9-451b-a594-4dbdff7f591d" xlink:to="loc_srt_SegmentGeographicalDomain_499c4c51-c2c9-451b-a594-4dbdff7f591d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_f1f6cefa-49dd-4881-bd8e-8afd01a7bfbd" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_499c4c51-c2c9-451b-a594-4dbdff7f591d" xlink:to="loc_srt_SegmentGeographicalDomain_f1f6cefa-49dd-4881-bd8e-8afd01a7bfbd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_8896053c-38a6-454c-a2b7-1ddcc1f9e0c5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_f1f6cefa-49dd-4881-bd8e-8afd01a7bfbd" xlink:to="loc_srt_AmericasMember_8896053c-38a6-454c-a2b7-1ddcc1f9e0c5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_c6a8a555-e3a0-46e3-a115-d7483d48cedd" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_f1f6cefa-49dd-4881-bd8e-8afd01a7bfbd" xlink:to="loc_country_CA_c6a8a555-e3a0-46e3-a115-d7483d48cedd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_4c7e7913-8105-4cb2-8e1c-a2a8e378d427" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_f1f6cefa-49dd-4881-bd8e-8afd01a7bfbd" xlink:to="loc_us-gaap_EMEAMember_4c7e7913-8105-4cb2-8e1c-a2a8e378d427" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_5867b893-3d6d-4f2f-94d1-911aba0a1e98" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_f1f6cefa-49dd-4881-bd8e-8afd01a7bfbd" xlink:to="loc_srt_AsiaPacificMember_5867b893-3d6d-4f2f-94d1-911aba0a1e98" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_9f3f2e35-e515-4323-885d-e9c8e97bc493" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_1713b632-4110-472d-b869-a678144453df" xlink:to="loc_srt_ProductOrServiceAxis_9f3f2e35-e515-4323-885d-e9c8e97bc493" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_9f3f2e35-e515-4323-885d-e9c8e97bc493_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_9f3f2e35-e515-4323-885d-e9c8e97bc493" xlink:to="loc_srt_ProductsAndServicesDomain_9f3f2e35-e515-4323-885d-e9c8e97bc493_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_312451d5-4393-4eea-a8f2-920dc4bdab57" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_9f3f2e35-e515-4323-885d-e9c8e97bc493" xlink:to="loc_srt_ProductsAndServicesDomain_312451d5-4393-4eea-a8f2-920dc4bdab57" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_f9fc1fb1-3f7e-44ac-bcb8-1f1a5d0fb25f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_312451d5-4393-4eea-a8f2-920dc4bdab57" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_f9fc1fb1-3f7e-44ac-bcb8-1f1a5d0fb25f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_841df395-3d99-47d1-b9c4-f66168616a73" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_312451d5-4393-4eea-a8f2-920dc4bdab57" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_841df395-3d99-47d1-b9c4-f66168616a73" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_7ff66aab-7f78-480d-a276-c65b978d6d95" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_1713b632-4110-472d-b869-a678144453df" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_7ff66aab-7f78-480d-a276-c65b978d6d95" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_7ff66aab-7f78-480d-a276-c65b978d6d95_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_7ff66aab-7f78-480d-a276-c65b978d6d95" xlink:to="loc_us-gaap_SegmentDomain_7ff66aab-7f78-480d-a276-c65b978d6d95_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_64c28927-489c-46f7-8d78-3271d99019d7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_7ff66aab-7f78-480d-a276-c65b978d6d95" xlink:to="loc_us-gaap_SegmentDomain_64c28927-489c-46f7-8d78-3271d99019d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_1bfc3f6a-18ba-45db-bf09-c175ef4153fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_64c28927-489c-46f7-8d78-3271d99019d7" xlink:to="loc_us-gaap_AllOtherSegmentsMember_1bfc3f6a-18ba-45db-bf09-c175ef4153fc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureGrossPremiumDiscountedBeforeReinsurance_deff388d-3162-490e-839e-97058abea4cd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureGrossPremiumDiscountedBeforeReinsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_4bd6fe2b-2acf-49cc-8f41-56c16a698911" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureGrossPremiumDiscountedBeforeReinsurance_deff388d-3162-490e-839e-97058abea4cd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitUndiscountedBeforeReinsurance_05c4d488-6ea2-433a-a623-adad3aaa6440" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitUndiscountedBeforeReinsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_4bd6fe2b-2acf-49cc-8f41-56c16a698911" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitUndiscountedBeforeReinsurance_05c4d488-6ea2-433a-a623-adad3aaa6440" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitDiscountedBeforeReinsurance_275cff77-d9ac-427d-b311-e085722e1450" xlink:href="rga-20240630.xsd#rga_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitDiscountedBeforeReinsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_4bd6fe2b-2acf-49cc-8f41-56c16a698911" xlink:to="loc_rga_LiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitDiscountedBeforeReinsurance_275cff77-d9ac-427d-b311-e085722e1450" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureGrossPremiumUndiscountedBeforeReinsurance_c9feeed8-6a33-41b9-84db-f7a7c2f011bd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureGrossPremiumUndiscountedBeforeReinsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_4bd6fe2b-2acf-49cc-8f41-56c16a698911" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitExpectedFutureGrossPremiumUndiscountedBeforeReinsurance_c9feeed8-6a33-41b9-84db-f7a7c2f011bd" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FuturePolicyBenefitsPremiumsandInterestDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FuturePolicyBenefitsPremiumsandInterestDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FuturePolicyBenefitsPremiumsandInterestDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_944664df-7aa9-4fed-9e11-cecc92143f19" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_8b204af3-7a1d-4a9d-a902-00f349a68f9e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitActivityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_944664df-7aa9-4fed-9e11-cecc92143f19" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_8b204af3-7a1d-4a9d-a902-00f349a68f9e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_9148ffa7-a2ed-4981-86b6-2513c0fca82f" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_8b204af3-7a1d-4a9d-a902-00f349a68f9e" xlink:to="loc_srt_MajorCustomersAxis_9148ffa7-a2ed-4981-86b6-2513c0fca82f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_9148ffa7-a2ed-4981-86b6-2513c0fca82f_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_9148ffa7-a2ed-4981-86b6-2513c0fca82f" xlink:to="loc_srt_NameOfMajorCustomerDomain_9148ffa7-a2ed-4981-86b6-2513c0fca82f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_79b6d3cc-0d3f-4b5d-af4e-a32445204eea" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_9148ffa7-a2ed-4981-86b6-2513c0fca82f" xlink:to="loc_srt_NameOfMajorCustomerDomain_79b6d3cc-0d3f-4b5d-af4e-a32445204eea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_78f10115-71ff-4438-ba7e-b74ef68548fb" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_8b204af3-7a1d-4a9d-a902-00f349a68f9e" xlink:to="loc_srt_StatementGeographicalAxis_78f10115-71ff-4438-ba7e-b74ef68548fb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_78f10115-71ff-4438-ba7e-b74ef68548fb_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_78f10115-71ff-4438-ba7e-b74ef68548fb" xlink:to="loc_srt_SegmentGeographicalDomain_78f10115-71ff-4438-ba7e-b74ef68548fb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_71fd6e38-6367-4bd0-a6a7-6f3b8874e582" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_78f10115-71ff-4438-ba7e-b74ef68548fb" xlink:to="loc_srt_SegmentGeographicalDomain_71fd6e38-6367-4bd0-a6a7-6f3b8874e582" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_b5b048b4-8ebc-44d9-827c-bbe97b3c17b4" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_71fd6e38-6367-4bd0-a6a7-6f3b8874e582" xlink:to="loc_srt_AmericasMember_b5b048b4-8ebc-44d9-827c-bbe97b3c17b4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_a867596b-c8d4-4b74-b293-0f666b1c8657" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_71fd6e38-6367-4bd0-a6a7-6f3b8874e582" xlink:to="loc_country_CA_a867596b-c8d4-4b74-b293-0f666b1c8657" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_d1638887-937c-4270-bace-78818b44ffd8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_71fd6e38-6367-4bd0-a6a7-6f3b8874e582" xlink:to="loc_us-gaap_EMEAMember_d1638887-937c-4270-bace-78818b44ffd8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_ee1fe9d6-d9fe-4078-9226-2a6e3e730fc3" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_71fd6e38-6367-4bd0-a6a7-6f3b8874e582" xlink:to="loc_srt_AsiaPacificMember_ee1fe9d6-d9fe-4078-9226-2a6e3e730fc3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_9cbea4b7-7d0f-4e79-b2ea-6615cc27e56f" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_8b204af3-7a1d-4a9d-a902-00f349a68f9e" xlink:to="loc_srt_ProductOrServiceAxis_9cbea4b7-7d0f-4e79-b2ea-6615cc27e56f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_9cbea4b7-7d0f-4e79-b2ea-6615cc27e56f_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_9cbea4b7-7d0f-4e79-b2ea-6615cc27e56f" xlink:to="loc_srt_ProductsAndServicesDomain_9cbea4b7-7d0f-4e79-b2ea-6615cc27e56f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_9acddc99-21f9-41e1-b9e8-10a28d9f1f1e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_9cbea4b7-7d0f-4e79-b2ea-6615cc27e56f" xlink:to="loc_srt_ProductsAndServicesDomain_9acddc99-21f9-41e1-b9e8-10a28d9f1f1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_c6d242d2-bb36-42bc-b109-b3f1632c3ce0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_9acddc99-21f9-41e1-b9e8-10a28d9f1f1e" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_c6d242d2-bb36-42bc-b109-b3f1632c3ce0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_0b8adf0b-502b-48b9-a2dc-fdd25c58f2c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_9acddc99-21f9-41e1-b9e8-10a28d9f1f1e" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_0b8adf0b-502b-48b9-a2dc-fdd25c58f2c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_9b2c30e7-597c-4132-a314-2b26c78bb90c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityTable_8b204af3-7a1d-4a9d-a902-00f349a68f9e" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_9b2c30e7-597c-4132-a314-2b26c78bb90c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_9b2c30e7-597c-4132-a314-2b26c78bb90c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_9b2c30e7-597c-4132-a314-2b26c78bb90c" xlink:to="loc_us-gaap_SegmentDomain_9b2c30e7-597c-4132-a314-2b26c78bb90c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_d53d01d7-c443-49a7-91d5-5f5f6c07d338" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_9b2c30e7-597c-4132-a314-2b26c78bb90c" xlink:to="loc_us-gaap_SegmentDomain_d53d01d7-c443-49a7-91d5-5f5f6c07d338" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_15b8bdc2-a5cd-4bf0-8c25-553efe45feff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_d53d01d7-c443-49a7-91d5-5f5f6c07d338" xlink:to="loc_us-gaap_AllOtherSegmentsMember_15b8bdc2-a5cd-4bf0-8c25-553efe45feff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitInterestExpense_0d52bf83-2ab2-48d0-a605-1535b43b10b5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitInterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_944664df-7aa9-4fed-9e11-cecc92143f19" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitInterestExpense_0d52bf83-2ab2-48d0-a605-1535b43b10b5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitGrossPremiumIncome_c2bbf058-d957-4320-be77-66527fca7461" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitGrossPremiumIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitActivityLineItems_944664df-7aa9-4fed-9e11-cecc92143f19" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitGrossPremiumIncome_c2bbf058-d957-4320-be77-66527fca7461" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FuturePolicyBenefitsAssumptionExplanationsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FuturePolicyBenefitsAssumptionExplanationsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FuturePolicyBenefitsAssumptionExplanationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_ddd3d97c-51b9-481d-a183-d50ad1bbe667" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_a8842e8d-87b8-4fca-b70e-a6e926f006d8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_ddd3d97c-51b9-481d-a183-d50ad1bbe667" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_a8842e8d-87b8-4fca-b70e-a6e926f006d8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_c1ff8604-b23f-4361-a358-63d71aacc16f" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_a8842e8d-87b8-4fca-b70e-a6e926f006d8" xlink:to="loc_srt_ProductOrServiceAxis_c1ff8604-b23f-4361-a358-63d71aacc16f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_c1ff8604-b23f-4361-a358-63d71aacc16f_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_c1ff8604-b23f-4361-a358-63d71aacc16f" xlink:to="loc_srt_ProductsAndServicesDomain_c1ff8604-b23f-4361-a358-63d71aacc16f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_4f5e2769-705e-4a06-be66-c3ab3715696a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_c1ff8604-b23f-4361-a358-63d71aacc16f" xlink:to="loc_srt_ProductsAndServicesDomain_4f5e2769-705e-4a06-be66-c3ab3715696a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_3fd12b19-20eb-42be-a06f-28d07883a2b8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_4f5e2769-705e-4a06-be66-c3ab3715696a" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_3fd12b19-20eb-42be-a06f-28d07883a2b8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_f2509f66-baf4-4655-aa53-4da368ca51a6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_4f5e2769-705e-4a06-be66-c3ab3715696a" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_f2509f66-baf4-4655-aa53-4da368ca51a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_16ac8c3d-5bff-4708-96f2-ff868368aeea" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_a8842e8d-87b8-4fca-b70e-a6e926f006d8" xlink:to="loc_srt_StatementGeographicalAxis_16ac8c3d-5bff-4708-96f2-ff868368aeea" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_16ac8c3d-5bff-4708-96f2-ff868368aeea_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_16ac8c3d-5bff-4708-96f2-ff868368aeea" xlink:to="loc_srt_SegmentGeographicalDomain_16ac8c3d-5bff-4708-96f2-ff868368aeea_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_7bacdf5d-8d7b-407e-9718-eff152aa8062" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_16ac8c3d-5bff-4708-96f2-ff868368aeea" xlink:to="loc_srt_SegmentGeographicalDomain_7bacdf5d-8d7b-407e-9718-eff152aa8062" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_23910fcf-92e8-493a-abd5-cb2519ef0870" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_7bacdf5d-8d7b-407e-9718-eff152aa8062" xlink:to="loc_srt_AmericasMember_23910fcf-92e8-493a-abd5-cb2519ef0870" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_ca82171a-0ec1-49ba-94b3-61b6d926accf" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_7bacdf5d-8d7b-407e-9718-eff152aa8062" xlink:to="loc_country_CA_ca82171a-0ec1-49ba-94b3-61b6d926accf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_3e5f3756-7cbb-4485-ace7-062d9eace7b1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_7bacdf5d-8d7b-407e-9718-eff152aa8062" xlink:to="loc_us-gaap_EMEAMember_3e5f3756-7cbb-4485-ace7-062d9eace7b1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_cf96699f-ddfe-49c2-92b7-ef9fa021d8fe" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_7bacdf5d-8d7b-407e-9718-eff152aa8062" xlink:to="loc_srt_AsiaPacificMember_cf96699f-ddfe-49c2-92b7-ef9fa021d8fe" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_19d486b1-85fb-4f8e-9a11-7a74bc4597b7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_a8842e8d-87b8-4fca-b70e-a6e926f006d8" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_19d486b1-85fb-4f8e-9a11-7a74bc4597b7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_19d486b1-85fb-4f8e-9a11-7a74bc4597b7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_19d486b1-85fb-4f8e-9a11-7a74bc4597b7" xlink:to="loc_us-gaap_SegmentDomain_19d486b1-85fb-4f8e-9a11-7a74bc4597b7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_64eba467-503b-4d58-8d54-b60728992d3c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_19d486b1-85fb-4f8e-9a11-7a74bc4597b7" xlink:to="loc_us-gaap_SegmentDomain_64eba467-503b-4d58-8d54-b60728992d3c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_b4464932-d5dd-4d92-88a7-a162f6dfe77b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_64eba467-503b-4d58-8d54-b60728992d3c" xlink:to="loc_us-gaap_AllOtherSegmentsMember_b4464932-d5dd-4d92-88a7-a162f6dfe77b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_NetLiabilityForFuturePolicyBenefitsAtOriginalDiscountRate_8886bc57-5084-4b04-83fb-f534659210ee" xlink:href="rga-20240630.xsd#rga_NetLiabilityForFuturePolicyBenefitsAtOriginalDiscountRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_ddd3d97c-51b9-481d-a183-d50ad1bbe667" xlink:to="loc_rga_NetLiabilityForFuturePolicyBenefitsAtOriginalDiscountRate_8886bc57-5084-4b04-83fb-f534659210ee" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FuturePolicyBenefitsActualToExpectedIncreaseDecrease_3e4a6731-4d58-4f90-a0c8-835bc32cfbde" xlink:href="rga-20240630.xsd#rga_FuturePolicyBenefitsActualToExpectedIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_ddd3d97c-51b9-481d-a183-d50ad1bbe667" xlink:to="loc_rga_FuturePolicyBenefitsActualToExpectedIncreaseDecrease_3e4a6731-4d58-4f90-a0c8-835bc32cfbde" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_IncreaseDecreaseImpactOfUpdatingDiscountRateRecognizedInOCI_efa61e58-d2da-4a13-8a1a-26199d9b9a6e" xlink:href="rga-20240630.xsd#rga_IncreaseDecreaseImpactOfUpdatingDiscountRateRecognizedInOCI"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_ddd3d97c-51b9-481d-a183-d50ad1bbe667" xlink:to="loc_rga_IncreaseDecreaseImpactOfUpdatingDiscountRateRecognizedInOCI_efa61e58-d2da-4a13-8a1a-26199d9b9a6e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FuturePolicyBenefitsActualToExpectedVarianceIncreaseDecrease_1748d879-75a5-41bb-b91f-ad8c5bef51c6" xlink:href="rga-20240630.xsd#rga_FuturePolicyBenefitsActualToExpectedVarianceIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_ddd3d97c-51b9-481d-a183-d50ad1bbe667" xlink:to="loc_rga_FuturePolicyBenefitsActualToExpectedVarianceIncreaseDecrease_1748d879-75a5-41bb-b91f-ad8c5bef51c6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ImpactOfUpdatingDiscountRateRecognizedInOCIIncreaseDecrease_05a73691-146d-45d4-9d5b-7a3d2adc5deb" xlink:href="rga-20240630.xsd#rga_ImpactOfUpdatingDiscountRateRecognizedInOCIIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_ddd3d97c-51b9-481d-a183-d50ad1bbe667" xlink:to="loc_rga_ImpactOfUpdatingDiscountRateRecognizedInOCIIncreaseDecrease_05a73691-146d-45d4-9d5b-7a3d2adc5deb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ChangesInCashFlowAssumptions_788acd53-32af-493f-aeec-11658f175b84" xlink:href="rga-20240630.xsd#rga_ChangesInCashFlowAssumptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_ddd3d97c-51b9-481d-a183-d50ad1bbe667" xlink:to="loc_rga_ChangesInCashFlowAssumptions_788acd53-32af-493f-aeec-11658f175b84" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FuturePolicyBenefitsDetailsNarrative" xlink:type="simple" xlink:href="rga-20240630.xsd#FuturePolicyBenefitsDetailsNarrative"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FuturePolicyBenefitsDetailsNarrative" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_243a5f63-93b6-4689-a639-ee3fe4779338" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_d2ceb977-a84e-484c-a61d-21cb08439d5e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_243a5f63-93b6-4689-a639-ee3fe4779338" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_d2ceb977-a84e-484c-a61d-21cb08439d5e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_01c3aab1-b1fc-4769-961b-b822a151b176" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_d2ceb977-a84e-484c-a61d-21cb08439d5e" xlink:to="loc_srt_ProductOrServiceAxis_01c3aab1-b1fc-4769-961b-b822a151b176" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01c3aab1-b1fc-4769-961b-b822a151b176_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_01c3aab1-b1fc-4769-961b-b822a151b176" xlink:to="loc_srt_ProductsAndServicesDomain_01c3aab1-b1fc-4769-961b-b822a151b176_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_235b8463-cde5-4ed6-acf3-88fc3931cdc9" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_01c3aab1-b1fc-4769-961b-b822a151b176" xlink:to="loc_srt_ProductsAndServicesDomain_235b8463-cde5-4ed6-acf3-88fc3931cdc9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_3a9ee422-42a0-49f2-ae6e-5e3c710d5c29" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_235b8463-cde5-4ed6-acf3-88fc3931cdc9" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_3a9ee422-42a0-49f2-ae6e-5e3c710d5c29" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_5962e18b-00ab-45b2-9255-0d7b4c7aea02" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_235b8463-cde5-4ed6-acf3-88fc3931cdc9" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_5962e18b-00ab-45b2-9255-0d7b4c7aea02" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_4f4b30de-91c7-4d5f-8174-e53dbe06afa1" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_d2ceb977-a84e-484c-a61d-21cb08439d5e" xlink:to="loc_srt_StatementGeographicalAxis_4f4b30de-91c7-4d5f-8174-e53dbe06afa1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_4f4b30de-91c7-4d5f-8174-e53dbe06afa1_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_4f4b30de-91c7-4d5f-8174-e53dbe06afa1" xlink:to="loc_srt_SegmentGeographicalDomain_4f4b30de-91c7-4d5f-8174-e53dbe06afa1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_7425bae6-b47d-48d5-ad2e-6e557e45a791" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_4f4b30de-91c7-4d5f-8174-e53dbe06afa1" xlink:to="loc_srt_SegmentGeographicalDomain_7425bae6-b47d-48d5-ad2e-6e557e45a791" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_ce33cf20-cf9d-4f5e-adfe-f26eab11ffb9" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_7425bae6-b47d-48d5-ad2e-6e557e45a791" xlink:to="loc_srt_AmericasMember_ce33cf20-cf9d-4f5e-adfe-f26eab11ffb9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_4d9838fd-8d0d-430e-9f93-89cdee018a7a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentTable_d2ceb977-a84e-484c-a61d-21cb08439d5e" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_4d9838fd-8d0d-430e-9f93-89cdee018a7a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_4d9838fd-8d0d-430e-9f93-89cdee018a7a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_4d9838fd-8d0d-430e-9f93-89cdee018a7a" xlink:to="loc_us-gaap_SegmentDomain_4d9838fd-8d0d-430e-9f93-89cdee018a7a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_59e08411-4b31-4a51-b8cc-a56ed4820c32" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_4d9838fd-8d0d-430e-9f93-89cdee018a7a" xlink:to="loc_us-gaap_SegmentDomain_59e08411-4b31-4a51-b8cc-a56ed4820c32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_5b05c5d5-e1c7-4e32-b745-abacf5e9035f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_59e08411-4b31-4a51-b8cc-a56ed4820c32" xlink:to="loc_us-gaap_AllOtherSegmentsMember_5b05c5d5-e1c7-4e32-b745-abacf5e9035f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ChangesInCashFlowAssumptions_082b2bd9-cb22-4b3b-9a20-5a4b389f8b47" xlink:href="rga-20240630.xsd#rga_ChangesInCashFlowAssumptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_243a5f63-93b6-4689-a639-ee3fe4779338" xlink:to="loc_rga_ChangesInCashFlowAssumptions_082b2bd9-cb22-4b3b-9a20-5a4b389f8b47" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitAfterReinsurance_967bc579-6b93-4d42-9257-6f9f9078ce12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitAfterReinsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_243a5f63-93b6-4689-a639-ee3fe4779338" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitAfterReinsurance_967bc579-6b93-4d42-9257-6f9f9078ce12" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForFuturePolicyBenefitReinsuranceRecoverableAfterAllowance_222b9dc6-e001-4e12-9f6d-cb1920da8f0d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilityForFuturePolicyBenefitReinsuranceRecoverableAfterAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForFuturePolicyBenefitByProductSegmentLineItems_243a5f63-93b6-4689-a639-ee3fe4779338" xlink:to="loc_us-gaap_LiabilityForFuturePolicyBenefitReinsuranceRecoverableAfterAllowance_222b9dc6-e001-4e12-9f6d-cb1920da8f0d" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/PolicyholderAccountBalancesAccountBalancesDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#PolicyholderAccountBalancesAccountBalancesDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/PolicyholderAccountBalancesAccountBalancesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceTable_a4b5e8ea-bef0-410c-9a20-be3cc2949c05" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderAccountBalanceTable_a4b5e8ea-bef0-410c-9a20-be3cc2949c05" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_d8a253a0-9f82-491c-9f04-3e45e9c4a7a8" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceTable_a4b5e8ea-bef0-410c-9a20-be3cc2949c05" xlink:to="loc_srt_ProductOrServiceAxis_d8a253a0-9f82-491c-9f04-3e45e9c4a7a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_d8a253a0-9f82-491c-9f04-3e45e9c4a7a8_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_d8a253a0-9f82-491c-9f04-3e45e9c4a7a8" xlink:to="loc_srt_ProductsAndServicesDomain_d8a253a0-9f82-491c-9f04-3e45e9c4a7a8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_de05dca2-407b-4eaa-9131-6b4303fd95b5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_d8a253a0-9f82-491c-9f04-3e45e9c4a7a8" xlink:to="loc_srt_ProductsAndServicesDomain_de05dca2-407b-4eaa-9131-6b4303fd95b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_0e7f365e-836c-4dbc-9b3d-502cc6018d51" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_de05dca2-407b-4eaa-9131-6b4303fd95b5" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_0e7f365e-836c-4dbc-9b3d-502cc6018d51" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_0928abfc-430e-4430-8cee-133684fc32e4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_de05dca2-407b-4eaa-9131-6b4303fd95b5" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_0928abfc-430e-4430-8cee-133684fc32e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_167458de-1de7-40a6-a65a-27916302496c" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceTable_a4b5e8ea-bef0-410c-9a20-be3cc2949c05" xlink:to="loc_srt_StatementGeographicalAxis_167458de-1de7-40a6-a65a-27916302496c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_167458de-1de7-40a6-a65a-27916302496c_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_167458de-1de7-40a6-a65a-27916302496c" xlink:to="loc_srt_SegmentGeographicalDomain_167458de-1de7-40a6-a65a-27916302496c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_ba7efa86-6a40-4dd1-a16f-e4f1743655a4" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_167458de-1de7-40a6-a65a-27916302496c" xlink:to="loc_srt_SegmentGeographicalDomain_ba7efa86-6a40-4dd1-a16f-e4f1743655a4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_7514d514-cdb5-4e4a-b9b9-b8e93d164d02" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ba7efa86-6a40-4dd1-a16f-e4f1743655a4" xlink:to="loc_srt_AmericasMember_7514d514-cdb5-4e4a-b9b9-b8e93d164d02" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_96df8487-ff40-4fa4-b4eb-edd602668933" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ba7efa86-6a40-4dd1-a16f-e4f1743655a4" xlink:to="loc_srt_AsiaPacificMember_96df8487-ff40-4fa4-b4eb-edd602668933" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_a7c9d67d-b044-43a0-93dc-c534ba286658" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceTable_a4b5e8ea-bef0-410c-9a20-be3cc2949c05" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_a7c9d67d-b044-43a0-93dc-c534ba286658" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfAdoptionMember_a7c9d67d-b044-43a0-93dc-c534ba286658_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TypeOfAdoptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_a7c9d67d-b044-43a0-93dc-c534ba286658" xlink:to="loc_us-gaap_TypeOfAdoptionMember_a7c9d67d-b044-43a0-93dc-c534ba286658_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfAdoptionMember_8270c291-223b-4ed5-865f-827a389cc0b9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TypeOfAdoptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_a7c9d67d-b044-43a0-93dc-c534ba286658" xlink:to="loc_us-gaap_TypeOfAdoptionMember_8270c291-223b-4ed5-865f-827a389cc0b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_bc287847-5855-4a82-8e3c-e93dfb473505" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceTable_a4b5e8ea-bef0-410c-9a20-be3cc2949c05" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_bc287847-5855-4a82-8e3c-e93dfb473505" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_bc287847-5855-4a82-8e3c-e93dfb473505_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_bc287847-5855-4a82-8e3c-e93dfb473505" xlink:to="loc_us-gaap_SegmentDomain_bc287847-5855-4a82-8e3c-e93dfb473505_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_5bdd5f2c-b6fb-4bed-8ce7-576b985c8021" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_bc287847-5855-4a82-8e3c-e93dfb473505" xlink:to="loc_us-gaap_SegmentDomain_5bdd5f2c-b6fb-4bed-8ce7-576b985c8021" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_f6301036-c7bb-43a9-87f1-0dc65b492b46" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_5bdd5f2c-b6fb-4bed-8ce7-576b985c8021" xlink:to="loc_us-gaap_AllOtherSegmentsMember_f6301036-c7bb-43a9-87f1-0dc65b492b46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_4e2c1731-706b-4f16-a87a-29e88b14d764" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceTable_a4b5e8ea-bef0-410c-9a20-be3cc2949c05" xlink:to="loc_srt_MajorCustomersAxis_4e2c1731-706b-4f16-a87a-29e88b14d764" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_4e2c1731-706b-4f16-a87a-29e88b14d764_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_4e2c1731-706b-4f16-a87a-29e88b14d764" xlink:to="loc_srt_NameOfMajorCustomerDomain_4e2c1731-706b-4f16-a87a-29e88b14d764_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_2046b138-9ff5-4b30-b9f5-8f535aea2fed" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_4e2c1731-706b-4f16-a87a-29e88b14d764" xlink:to="loc_srt_NameOfMajorCustomerDomain_2046b138-9ff5-4b30-b9f5-8f535aea2fed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderFunds_aaceb491-a70e-484f-8e21-0c7bbc672ba6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderFunds"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderFunds_aaceb491-a70e-484f-8e21-0c7bbc672ba6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceIssuance_3b88b643-6f43-4858-8d9a-8ffdeee550e0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceIssuance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderAccountBalanceIssuance_3b88b643-6f43-4858-8d9a-8ffdeee550e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalancePolicyCharge_61647de3-fa8c-4253-999b-0769b373d509" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalancePolicyCharge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderAccountBalancePolicyCharge_61647de3-fa8c-4253-999b-0769b373d509" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceSurrenderAndWithdrawal_0204e719-d71e-4844-a03c-1b9c109ff148" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceSurrenderAndWithdrawal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderAccountBalanceSurrenderAndWithdrawal_0204e719-d71e-4844-a03c-1b9c109ff148" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceBenefitPayment_fb497c38-74e6-435a-995e-dd71cd5b8ec5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceBenefitPayment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderAccountBalanceBenefitPayment_fb497c38-74e6-435a-995e-dd71cd5b8ec5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestCreditedToPolicyholdersAccountBalances_4ff52f51-7513-4003-bd2a-f7f01f163e9b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestCreditedToPolicyholdersAccountBalances"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_InterestCreditedToPolicyholdersAccountBalances_4ff52f51-7513-4003-bd2a-f7f01f163e9b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PolicyholderAccountBalanceForeignCurrencyTranslation_d28c366d-41e8-4518-8d09-4ba67a2726fb" xlink:href="rga-20240630.xsd#rga_PolicyholderAccountBalanceForeignCurrencyTranslation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_rga_PolicyholderAccountBalanceForeignCurrencyTranslation_d28c366d-41e8-4518-8d09-4ba67a2726fb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PolicyholderAccountBalanceReinsuranceRecoverable_6bb24990-d03c-40f3-914c-e464b74f0037" xlink:href="rga-20240630.xsd#rga_PolicyholderAccountBalanceReinsuranceRecoverable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_rga_PolicyholderAccountBalanceReinsuranceRecoverable_6bb24990-d03c-40f3-914c-e464b74f0037" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PolicyholderAccountBalanceAfterReinsurance_498fc9f8-3b8d-4d02-b22d-114c8d34d5e0" xlink:href="rga-20240630.xsd#rga_PolicyholderAccountBalanceAfterReinsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_rga_PolicyholderAccountBalanceAfterReinsurance_498fc9f8-3b8d-4d02-b22d-114c8d34d5e0" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceNetAmountAtRisk_4ff54143-a63a-4362-9773-9195c8cd43f4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceNetAmountAtRisk"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderAccountBalanceNetAmountAtRisk_4ff54143-a63a-4362-9773-9195c8cd43f4" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashSurrenderValueDuePolicyholdersAmount_f48827a1-4976-4f38-a85a-4dfc8453e557" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashSurrenderValueDuePolicyholdersAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_CashSurrenderValueDuePolicyholdersAmount_f48827a1-4976-4f38-a85a-4dfc8453e557" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceWeightedAverageCreditingRate_0df701fd-82e1-4a34-b244-bf2994d7b770" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceWeightedAverageCreditingRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderAccountBalanceWeightedAverageCreditingRate_0df701fd-82e1-4a34-b244-bf2994d7b770" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceIncreaseDecreaseFromOtherChange_cf056288-13e7-4aba-8706-cbe91085cb73" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceIncreaseDecreaseFromOtherChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceLineItems_49f4653b-2d41-45e4-9320-259e0ec32550" xlink:to="loc_us-gaap_PolicyholderAccountBalanceIncreaseDecreaseFromOtherChange_cf056288-13e7-4aba-8706-cbe91085cb73" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/PolicyholderAccountBalancesGuaranteedMinimumDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#PolicyholderAccountBalancesGuaranteedMinimumDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/PolicyholderAccountBalancesGuaranteedMinimumDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateLineItems_01ee5981-5d0e-4cd7-b53c-25ede1713257" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateLineItems_01ee5981-5d0e-4cd7-b53c-25ede1713257" xlink:to="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_c6cf97f4-10d7-459b-b1d0-ffb2afb51160" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:to="loc_srt_MajorCustomersAxis_c6cf97f4-10d7-459b-b1d0-ffb2afb51160" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_c6cf97f4-10d7-459b-b1d0-ffb2afb51160_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_c6cf97f4-10d7-459b-b1d0-ffb2afb51160" xlink:to="loc_srt_NameOfMajorCustomerDomain_c6cf97f4-10d7-459b-b1d0-ffb2afb51160_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_11c28565-d869-429e-98ec-a50cf14e422d" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_c6cf97f4-10d7-459b-b1d0-ffb2afb51160" xlink:to="loc_srt_NameOfMajorCustomerDomain_11c28565-d869-429e-98ec-a50cf14e422d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_fec0f43e-37f7-4e09-aaac-b9ae449407e3" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:to="loc_srt_StatementGeographicalAxis_fec0f43e-37f7-4e09-aaac-b9ae449407e3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_fec0f43e-37f7-4e09-aaac-b9ae449407e3_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_fec0f43e-37f7-4e09-aaac-b9ae449407e3" xlink:to="loc_srt_SegmentGeographicalDomain_fec0f43e-37f7-4e09-aaac-b9ae449407e3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_a0c7cdfd-b0f0-468c-8a70-214b625a0779" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_fec0f43e-37f7-4e09-aaac-b9ae449407e3" xlink:to="loc_srt_SegmentGeographicalDomain_a0c7cdfd-b0f0-468c-8a70-214b625a0779" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_d493413b-e0a9-4a12-9768-2811d36cc0f6" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a0c7cdfd-b0f0-468c-8a70-214b625a0779" xlink:to="loc_srt_AmericasMember_d493413b-e0a9-4a12-9768-2811d36cc0f6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_11e68706-dfb0-4371-99dc-525497d289e2" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a0c7cdfd-b0f0-468c-8a70-214b625a0779" xlink:to="loc_srt_AsiaPacificMember_11e68706-dfb0-4371-99dc-525497d289e2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_71b4bef2-dbab-439d-af74-d1be34724fff" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:to="loc_srt_ProductOrServiceAxis_71b4bef2-dbab-439d-af74-d1be34724fff" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_71b4bef2-dbab-439d-af74-d1be34724fff_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_71b4bef2-dbab-439d-af74-d1be34724fff" xlink:to="loc_srt_ProductsAndServicesDomain_71b4bef2-dbab-439d-af74-d1be34724fff_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_8789cbf5-bed6-4900-9c83-f9ce51611d48" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_71b4bef2-dbab-439d-af74-d1be34724fff" xlink:to="loc_srt_ProductsAndServicesDomain_8789cbf5-bed6-4900-9c83-f9ce51611d48" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_d9dc47ed-0ecd-44fd-be83-85457d52cb35" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_8789cbf5-bed6-4900-9c83-f9ce51611d48" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_d9dc47ed-0ecd-44fd-be83-85457d52cb35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_76016154-0f14-4377-ba47-858dded43a78" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_8789cbf5-bed6-4900-9c83-f9ce51611d48" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_76016154-0f14-4377-ba47-858dded43a78" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_1848a23b-16e0-4e8c-a482-053c049ff900" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_1848a23b-16e0-4e8c-a482-053c049ff900" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_1848a23b-16e0-4e8c-a482-053c049ff900_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_1848a23b-16e0-4e8c-a482-053c049ff900" xlink:to="loc_us-gaap_SegmentDomain_1848a23b-16e0-4e8c-a482-053c049ff900_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_684de2f6-c6ba-4a90-93f2-0d29edb70d4f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_1848a23b-16e0-4e8c-a482-053c049ff900" xlink:to="loc_us-gaap_SegmentDomain_684de2f6-c6ba-4a90-93f2-0d29edb70d4f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_d5a9db6c-55c2-42d6-899a-e0e6f6dbefa1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_684de2f6-c6ba-4a90-93f2-0d29edb70d4f" xlink:to="loc_us-gaap_AllOtherSegmentsMember_d5a9db6c-55c2-42d6-899a-e0e6f6dbefa1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_ac5b99fc-6a4f-4f56-835d-ff06f0cbee9e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:to="loc_srt_RangeAxis_ac5b99fc-6a4f-4f56-835d-ff06f0cbee9e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_ac5b99fc-6a4f-4f56-835d-ff06f0cbee9e_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_ac5b99fc-6a4f-4f56-835d-ff06f0cbee9e" xlink:to="loc_srt_RangeMember_ac5b99fc-6a4f-4f56-835d-ff06f0cbee9e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_98f02c5a-22d1-4b56-af8e-33917caa8158" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_ac5b99fc-6a4f-4f56-835d-ff06f0cbee9e" xlink:to="loc_srt_RangeMember_98f02c5a-22d1-4b56-af8e-33917caa8158" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeAxis_f18f44c0-07e2-4c81-b467-0898bc2f67d3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:to="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeAxis_f18f44c0-07e2-4c81-b467-0898bc2f67d3" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_f18f44c0-07e2-4c81-b467-0898bc2f67d3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeAxis_f18f44c0-07e2-4c81-b467-0898bc2f67d3" xlink:to="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_f18f44c0-07e2-4c81-b467-0898bc2f67d3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_74cc2074-d749-4c46-b340-a06d53a13fe8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeAxis_f18f44c0-07e2-4c81-b467-0898bc2f67d3" xlink:to="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_74cc2074-d749-4c46-b340-a06d53a13fe8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0200To0299Member_390eefb0-8817-49ca-aef8-c50294901d16" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0200To0299Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_74cc2074-d749-4c46-b340-a06d53a13fe8" xlink:to="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0200To0299Member_390eefb0-8817-49ca-aef8-c50294901d16" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0300To0399Member_b649bfbf-7873-4581-bd0b-08430e8b4093" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0300To0399Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_74cc2074-d749-4c46-b340-a06d53a13fe8" xlink:to="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0300To0399Member_b649bfbf-7873-4581-bd0b-08430e8b4093" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0400AndGreaterMember_6c7a31e1-e920-4700-bc31-864bbc7308dd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0400AndGreaterMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_74cc2074-d749-4c46-b340-a06d53a13fe8" xlink:to="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0400AndGreaterMember_6c7a31e1-e920-4700-bc31-864bbc7308dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeLessThan100MemberMember_6e5a8135-dbec-4e43-aa15-73d77ca5e163" xlink:href="rga-20240630.xsd#rga_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeLessThan100MemberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_74cc2074-d749-4c46-b340-a06d53a13fe8" xlink:to="loc_rga_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeLessThan100MemberMember_6e5a8135-dbec-4e43-aa15-73d77ca5e163" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0100To0199MemberMember_31b19c50-fe52-483f-a428-60f4a974272a" xlink:href="rga-20240630.xsd#rga_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0100To0199MemberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeDomain_74cc2074-d749-4c46-b340-a06d53a13fe8" xlink:to="loc_rga_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateRangeFrom0100To0199MemberMember_31b19c50-fe52-483f-a428-60f4a974272a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateAxis_391f1fcd-6b76-4abc-8574-8ac52abf6346" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateTable_188a57aa-43bb-497c-9132-50a13322d1a8" xlink:to="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateAxis_391f1fcd-6b76-4abc-8574-8ac52abf6346" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_391f1fcd-6b76-4abc-8574-8ac52abf6346_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateAxis_391f1fcd-6b76-4abc-8574-8ac52abf6346" xlink:to="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_391f1fcd-6b76-4abc-8574-8ac52abf6346_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_4c999e2c-29b0-412c-9ce1-17803c8f94e4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateAxis_391f1fcd-6b76-4abc-8574-8ac52abf6346" xlink:to="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_4c999e2c-29b0-412c-9ce1-17803c8f94e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceAtGuaranteedMinimumCreditingRateMember_82f74ecd-4842-41c8-91b3-98f87467bcbe" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceAtGuaranteedMinimumCreditingRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_4c999e2c-29b0-412c-9ce1-17803c8f94e4" xlink:to="loc_us-gaap_PolicyholderAccountBalanceAtGuaranteedMinimumCreditingRateMember_82f74ecd-4842-41c8-91b3-98f87467bcbe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0001To0050Member_84d9bad9-4591-487f-8a3f-90f9e5750a32" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0001To0050Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_4c999e2c-29b0-412c-9ce1-17803c8f94e4" xlink:to="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0001To0050Member_84d9bad9-4591-487f-8a3f-90f9e5750a32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0051To0150Member_beda1840-f4ba-4ad1-8f7a-67ed8eee6159" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0051To0150Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_4c999e2c-29b0-412c-9ce1-17803c8f94e4" xlink:to="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0051To0150Member_beda1840-f4ba-4ad1-8f7a-67ed8eee6159" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0151AndGreaterMember_18b0a5b4-39ac-4b3a-9cee-d59409ee8f16" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0151AndGreaterMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_4c999e2c-29b0-412c-9ce1-17803c8f94e4" xlink:to="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0151AndGreaterMember_18b0a5b4-39ac-4b3a-9cee-d59409ee8f16" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0051To0100Member_4b8ce1dc-7249-4e16-968c-2574b15daee0" xlink:href="rga-20240630.xsd#rga_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0051To0100Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateDomain_4c999e2c-29b0-412c-9ce1-17803c8f94e4" xlink:to="loc_rga_PolicyholderAccountBalanceAboveGuaranteedMinimumCreditingRateRangeFrom0051To0100Member_4b8ce1dc-7249-4e16-968c-2574b15daee0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderFunds_721270c1-9c6e-49c1-b7e2-b8df937e420d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyholderFunds"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PolicyholderAccountBalanceGuaranteedMinimumCreditingRateLineItems_01ee5981-5d0e-4cd7-b53c-25ede1713257" xlink:to="loc_us-gaap_PolicyholderFunds_721270c1-9c6e-49c1-b7e2-b8df937e420d" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/MarketRiskBenefitsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#MarketRiskBenefitsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/MarketRiskBenefitsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitTable_a3c435dc-f6d4-4354-af3e-531acd677a10" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitTable_a3c435dc-f6d4-4354-af3e-531acd677a10" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_a274786f-96ac-4dee-bd7f-064bacd65eb8" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_a3c435dc-f6d4-4354-af3e-531acd677a10" xlink:to="loc_srt_ProductOrServiceAxis_a274786f-96ac-4dee-bd7f-064bacd65eb8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_a274786f-96ac-4dee-bd7f-064bacd65eb8_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_a274786f-96ac-4dee-bd7f-064bacd65eb8" xlink:to="loc_srt_ProductsAndServicesDomain_a274786f-96ac-4dee-bd7f-064bacd65eb8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_a6d0b8ab-b54f-477d-8e4d-8e10e1c1726a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_a274786f-96ac-4dee-bd7f-064bacd65eb8" xlink:to="loc_srt_ProductsAndServicesDomain_a6d0b8ab-b54f-477d-8e4d-8e10e1c1726a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_325dc5c2-95e7-463b-a459-4f6da4a741de" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_a6d0b8ab-b54f-477d-8e4d-8e10e1c1726a" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_325dc5c2-95e7-463b-a459-4f6da4a741de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_8a153f31-57f2-4bae-ba3b-f4f67e469782" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_a3c435dc-f6d4-4354-af3e-531acd677a10" xlink:to="loc_srt_StatementGeographicalAxis_8a153f31-57f2-4bae-ba3b-f4f67e469782" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_8a153f31-57f2-4bae-ba3b-f4f67e469782_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_8a153f31-57f2-4bae-ba3b-f4f67e469782" xlink:to="loc_srt_SegmentGeographicalDomain_8a153f31-57f2-4bae-ba3b-f4f67e469782_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_97a0803b-2812-4865-a366-75021d6097d3" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_8a153f31-57f2-4bae-ba3b-f4f67e469782" xlink:to="loc_srt_SegmentGeographicalDomain_97a0803b-2812-4865-a366-75021d6097d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_a2130888-6a77-45f5-b806-5bc77549bbcd" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_97a0803b-2812-4865-a366-75021d6097d3" xlink:to="loc_srt_AmericasMember_a2130888-6a77-45f5-b806-5bc77549bbcd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_25b523ac-b521-4468-be98-a34e7e614280" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_a3c435dc-f6d4-4354-af3e-531acd677a10" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_25b523ac-b521-4468-be98-a34e7e614280" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_25b523ac-b521-4468-be98-a34e7e614280_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_25b523ac-b521-4468-be98-a34e7e614280" xlink:to="loc_us-gaap_SegmentDomain_25b523ac-b521-4468-be98-a34e7e614280_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_14103451-fca2-4e0c-88ff-75d5de3ecd74" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_25b523ac-b521-4468-be98-a34e7e614280" xlink:to="loc_us-gaap_SegmentDomain_14103451-fca2-4e0c-88ff-75d5de3ecd74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_f2cfdfe1-5088-4717-8be1-99620ca9b4f2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_14103451-fca2-4e0c-88ff-75d5de3ecd74" xlink:to="loc_us-gaap_AllOtherSegmentsMember_f2cfdfe1-5088-4717-8be1-99620ca9b4f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis_091def30-f6f6-4246-8db2-353dc821d67e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_a3c435dc-f6d4-4354-af3e-531acd677a10" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis_091def30-f6f6-4246-8db2-353dc821d67e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain_091def30-f6f6-4246-8db2-353dc821d67e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis_091def30-f6f6-4246-8db2-353dc821d67e" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain_091def30-f6f6-4246-8db2-353dc821d67e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain_92c0bd78-dc0b-49fa-9e5b-297a45da5659" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis_091def30-f6f6-4246-8db2-353dc821d67e" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain_92c0bd78-dc0b-49fa-9e5b-297a45da5659" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis_90490a36-4720-4385-95f4-2f065080c5c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_a3c435dc-f6d4-4354-af3e-531acd677a10" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis_90490a36-4720-4385-95f4-2f065080c5c9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain_90490a36-4720-4385-95f4-2f065080c5c9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis_90490a36-4720-4385-95f4-2f065080c5c9" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain_90490a36-4720-4385-95f4-2f065080c5c9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain_28167838-aa31-4ac7-8fd4-abbef04ddf44" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis_90490a36-4720-4385-95f4-2f065080c5c9" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain_28167838-aa31-4ac7-8fd4-abbef04ddf44" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_71c7295b-af3f-4eac-b5af-52c757487f47" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_a3c435dc-f6d4-4354-af3e-531acd677a10" xlink:to="loc_srt_MajorCustomersAxis_71c7295b-af3f-4eac-b5af-52c757487f47" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_71c7295b-af3f-4eac-b5af-52c757487f47_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_71c7295b-af3f-4eac-b5af-52c757487f47" xlink:to="loc_srt_NameOfMajorCustomerDomain_71c7295b-af3f-4eac-b5af-52c757487f47_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_e66d9a5e-957a-45eb-9b01-12a79346bc67" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_71c7295b-af3f-4eac-b5af-52c757487f47" xlink:to="loc_srt_NameOfMajorCustomerDomain_e66d9a5e-957a-45eb-9b01-12a79346bc67" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitAfterReinsuranceAndCumulativeIncreaseDecreaseFromInstrumentSpecificCreditRiskChange_3ca0eec3-6617-4a9f-94c3-b93837a4f10a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitAfterReinsuranceAndCumulativeIncreaseDecreaseFromInstrumentSpecificCreditRiskChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitAfterReinsuranceAndCumulativeIncreaseDecreaseFromInstrumentSpecificCreditRiskChange_3ca0eec3-6617-4a9f-94c3-b93837a4f10a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitBeforeReinsuranceAndCumulativeIncreaseDecreaseFromInstrumentSpecificCreditRiskChange_e3fc2312-d360-4006-be49-884cefd4c820" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitBeforeReinsuranceAndCumulativeIncreaseDecreaseFromInstrumentSpecificCreditRiskChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitBeforeReinsuranceAndCumulativeIncreaseDecreaseFromInstrumentSpecificCreditRiskChange_e3fc2312-d360-4006-be49-884cefd4c820" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitInterestExpense_e8f379b5-2a4b-48ba-a57d-04b4a9d55ace" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitInterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitInterestExpense_e8f379b5-2a4b-48ba-a57d-04b4a9d55ace" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitAttributedFeeCollected_0cfc24af-8368-45b2-bc2b-d0e0534eb111" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitAttributedFeeCollected"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitAttributedFeeCollected_0cfc24af-8368-45b2-bc2b-d0e0534eb111" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitBenefitPayment_fc0bc8f2-830b-458f-83e3-8a6b575b5381" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitBenefitPayment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitBenefitPayment_fc0bc8f2-830b-458f-83e3-8a6b575b5381" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromInterestRateChange_98b83fbd-6c59-47fc-9952-e38552b4fb8e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitIncreaseDecreaseFromInterestRateChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromInterestRateChange_98b83fbd-6c59-47fc-9952-e38552b4fb8e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromEquityMarketChange_fad66647-30ef-4113-9603-46c428df400d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitIncreaseDecreaseFromEquityMarketChange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromEquityMarketChange_fad66647-30ef-4113-9603-46c428df400d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromVolatility_da87c15f-4ccb-401b-9cdc-522c7f017300" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitIncreaseDecreaseFromVolatility"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromVolatility_da87c15f-4ccb-401b-9cdc-522c7f017300" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromOtherAssumption_278d2f72-ae12-42c7-98e9-947823351c0d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitIncreaseDecreaseFromOtherAssumption"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromOtherAssumption_278d2f72-ae12-42c7-98e9-947823351c0d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromActualPolicyholderBehaviorDifferentFromExpected_b860807e-9ac4-4d4f-b84e-2604e56ffacb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitIncreaseDecreaseFromActualPolicyholderBehaviorDifferentFromExpected"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitIncreaseDecreaseFromActualPolicyholderBehaviorDifferentFromExpected_b860807e-9ac4-4d4f-b84e-2604e56ffacb" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociMarketRiskBenefitInstrumentSpecificCreditRiskBeforeTax_48ad262f-0793-420b-9553-e17204a54638" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AociMarketRiskBenefitInstrumentSpecificCreditRiskBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_AociMarketRiskBenefitInstrumentSpecificCreditRiskBeforeTax_48ad262f-0793-420b-9553-e17204a54638" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitAfterIncreaseDecreaseFromInstrumentSpecificCreditRisk_4a1ef1a3-9959-41d4-a1a0-2d26e66d3359" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitAfterIncreaseDecreaseFromInstrumentSpecificCreditRisk"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitAfterIncreaseDecreaseFromInstrumentSpecificCreditRisk_4a1ef1a3-9959-41d4-a1a0-2d26e66d3359" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitReinsuranceRecoverableAfterAllowance_bbdb117c-e8af-4b95-b8be-3e7874651f9f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitReinsuranceRecoverableAfterAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitReinsuranceRecoverableAfterAllowance_bbdb117c-e8af-4b95-b8be-3e7874651f9f" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitNetAmountAtRisk_491d2a3f-0198-48a3-b751-b0c305005d68" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitNetAmountAtRisk"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_MarketRiskBenefitNetAmountAtRisk_491d2a3f-0198-48a3-b751-b0c305005d68" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetAmountAtRiskByProductAndGuaranteeWeightedAverageAttainedAge1_dd103b34-2dba-4853-a65d-481b85fdc40e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetAmountAtRiskByProductAndGuaranteeWeightedAverageAttainedAge1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_5187b623-8c22-46ee-89fe-644dedf47385" xlink:to="loc_us-gaap_NetAmountAtRiskByProductAndGuaranteeWeightedAverageAttainedAge1_dd103b34-2dba-4853-a65d-481b85fdc40e" xlink:type="arc" order="14"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/MarketRiskBenefitsInstrumentSpecificCreditRiskDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#MarketRiskBenefitsInstrumentSpecificCreditRiskDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/MarketRiskBenefitsInstrumentSpecificCreditRiskDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitLineItems_9721905c-5691-4e3e-861c-a536cae8dc9f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitTable_70ea7d4f-b9c1-4e09-8042-c71887eb340b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_9721905c-5691-4e3e-861c-a536cae8dc9f" xlink:to="loc_us-gaap_MarketRiskBenefitTable_70ea7d4f-b9c1-4e09-8042-c71887eb340b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_0ad054f9-eb3d-4345-970d-b0c9d3207398" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_70ea7d4f-b9c1-4e09-8042-c71887eb340b" xlink:to="loc_srt_ProductOrServiceAxis_0ad054f9-eb3d-4345-970d-b0c9d3207398" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_0ad054f9-eb3d-4345-970d-b0c9d3207398_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_0ad054f9-eb3d-4345-970d-b0c9d3207398" xlink:to="loc_srt_ProductsAndServicesDomain_0ad054f9-eb3d-4345-970d-b0c9d3207398_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_b189ba9a-ef41-45da-875e-ecd09fabcb0c" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_0ad054f9-eb3d-4345-970d-b0c9d3207398" xlink:to="loc_srt_ProductsAndServicesDomain_b189ba9a-ef41-45da-875e-ecd09fabcb0c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_91ee41cc-7f57-4e91-89ca-2b7f29ab1af2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_b189ba9a-ef41-45da-875e-ecd09fabcb0c" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_91ee41cc-7f57-4e91-89ca-2b7f29ab1af2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_ca086949-fc98-49bb-8a9e-2ac92acdf605" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_70ea7d4f-b9c1-4e09-8042-c71887eb340b" xlink:to="loc_srt_StatementGeographicalAxis_ca086949-fc98-49bb-8a9e-2ac92acdf605" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_ca086949-fc98-49bb-8a9e-2ac92acdf605_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_ca086949-fc98-49bb-8a9e-2ac92acdf605" xlink:to="loc_srt_SegmentGeographicalDomain_ca086949-fc98-49bb-8a9e-2ac92acdf605_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_f76dd135-6bb6-4871-b737-569a90d91678" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_ca086949-fc98-49bb-8a9e-2ac92acdf605" xlink:to="loc_srt_SegmentGeographicalDomain_f76dd135-6bb6-4871-b737-569a90d91678" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_640f8ddc-579b-42c8-ab55-14c5dccd8894" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_f76dd135-6bb6-4871-b737-569a90d91678" xlink:to="loc_srt_AmericasMember_640f8ddc-579b-42c8-ab55-14c5dccd8894" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_aebfa94d-6faf-4086-9c80-d1b67f7a86ee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_70ea7d4f-b9c1-4e09-8042-c71887eb340b" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_aebfa94d-6faf-4086-9c80-d1b67f7a86ee" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_aebfa94d-6faf-4086-9c80-d1b67f7a86ee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_aebfa94d-6faf-4086-9c80-d1b67f7a86ee" xlink:to="loc_us-gaap_SegmentDomain_aebfa94d-6faf-4086-9c80-d1b67f7a86ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_a87d504d-90b4-4d45-8e36-6b0819b3f9ff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_aebfa94d-6faf-4086-9c80-d1b67f7a86ee" xlink:to="loc_us-gaap_SegmentDomain_a87d504d-90b4-4d45-8e36-6b0819b3f9ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_617e627c-85b4-438d-87a6-acb2f79b48df" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_a87d504d-90b4-4d45-8e36-6b0819b3f9ff" xlink:to="loc_us-gaap_AllOtherSegmentsMember_617e627c-85b4-438d-87a6-acb2f79b48df" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis_9b74a807-61c0-4536-8421-2295abd251ab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_70ea7d4f-b9c1-4e09-8042-c71887eb340b" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis_9b74a807-61c0-4536-8421-2295abd251ab" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain_9b74a807-61c0-4536-8421-2295abd251ab_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis_9b74a807-61c0-4536-8421-2295abd251ab" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain_9b74a807-61c0-4536-8421-2295abd251ab_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain_7278c63a-a9d0-4681-ab22-bd8559c85a39" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitAxis_9b74a807-61c0-4536-8421-2295abd251ab" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfBenefitDomain_7278c63a-a9d0-4681-ab22-bd8559c85a39" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis_74947bf5-c6ae-4dc2-b282-5884f5c8a347" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_70ea7d4f-b9c1-4e09-8042-c71887eb340b" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis_74947bf5-c6ae-4dc2-b282-5884f5c8a347" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain_74947bf5-c6ae-4dc2-b282-5884f5c8a347_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis_74947bf5-c6ae-4dc2-b282-5884f5c8a347" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain_74947bf5-c6ae-4dc2-b282-5884f5c8a347_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain_0e3bd8d4-a9bb-4240-8a2c-0f8801aba6cb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeAxis_74947bf5-c6ae-4dc2-b282-5884f5c8a347" xlink:to="loc_us-gaap_GuaranteedInsuranceContractTypeOfGuaranteeDomain_0e3bd8d4-a9bb-4240-8a2c-0f8801aba6cb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_528f922b-7a9d-4ccf-ba95-2ab77fe9a0c4" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketRiskBenefitTable_70ea7d4f-b9c1-4e09-8042-c71887eb340b" xlink:to="loc_srt_MajorCustomersAxis_528f922b-7a9d-4ccf-ba95-2ab77fe9a0c4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_528f922b-7a9d-4ccf-ba95-2ab77fe9a0c4_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_528f922b-7a9d-4ccf-ba95-2ab77fe9a0c4" xlink:to="loc_srt_NameOfMajorCustomerDomain_528f922b-7a9d-4ccf-ba95-2ab77fe9a0c4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_deb47627-a7b3-437f-a438-170cd7cd0da5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_528f922b-7a9d-4ccf-ba95-2ab77fe9a0c4" xlink:to="loc_srt_NameOfMajorCustomerDomain_deb47627-a7b3-437f-a438-170cd7cd0da5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitAfterIncreaseDecreaseFromInstrumentSpecificCreditRisk_f143bede-984c-459b-ab4e-a6e7bd5d2114" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitAfterIncreaseDecreaseFromInstrumentSpecificCreditRisk"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_9721905c-5691-4e3e-861c-a536cae8dc9f" xlink:to="loc_us-gaap_MarketRiskBenefitAfterIncreaseDecreaseFromInstrumentSpecificCreditRisk_f143bede-984c-459b-ab4e-a6e7bd5d2114" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitAssetAmount_89df342e-dd99-4416-bc2b-f5cad731f503" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitAssetAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_9721905c-5691-4e3e-861c-a536cae8dc9f" xlink:to="loc_us-gaap_MarketRiskBenefitAssetAmount_89df342e-dd99-4416-bc2b-f5cad731f503" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketRiskBenefitLiabilityAmount_023840ba-54dd-434e-9087-8549ea345ea2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketRiskBenefitLiabilityAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketRiskBenefitLineItems_9721905c-5691-4e3e-861c-a536cae8dc9f" xlink:to="loc_us-gaap_MarketRiskBenefitLiabilityAmount_023840ba-54dd-434e-9087-8549ea345ea2" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DeferredPolicyAcquisitionCostsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DeferredPolicyAcquisitionCostsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DeferredPolicyAcquisitionCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostLineItems_0c6e9923-2846-4252-9556-1f1d8e8f199f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredPolicyAcquisitionCostLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostTable_60fc7fc5-7c43-4f52-8f43-c48ddf78847a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredPolicyAcquisitionCostTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostLineItems_0c6e9923-2846-4252-9556-1f1d8e8f199f" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostTable_60fc7fc5-7c43-4f52-8f43-c48ddf78847a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_e5b633ff-226b-40b8-a6fa-e513860f061d" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostTable_60fc7fc5-7c43-4f52-8f43-c48ddf78847a" xlink:to="loc_srt_ProductOrServiceAxis_e5b633ff-226b-40b8-a6fa-e513860f061d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_e5b633ff-226b-40b8-a6fa-e513860f061d_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_e5b633ff-226b-40b8-a6fa-e513860f061d" xlink:to="loc_srt_ProductsAndServicesDomain_e5b633ff-226b-40b8-a6fa-e513860f061d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_bfef64f5-d99a-49f7-9002-8381b7254a96" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_e5b633ff-226b-40b8-a6fa-e513860f061d" xlink:to="loc_srt_ProductsAndServicesDomain_bfef64f5-d99a-49f7-9002-8381b7254a96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_08599386-9100-4756-b817-657f77c9a60c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_bfef64f5-d99a-49f7-9002-8381b7254a96" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_08599386-9100-4756-b817-657f77c9a60c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInsuranceProductLineMember_0b6880ee-b789-4672-a287-6f868bf2b452" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInsuranceProductLineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_bfef64f5-d99a-49f7-9002-8381b7254a96" xlink:to="loc_us-gaap_OtherInsuranceProductLineMember_0b6880ee-b789-4672-a287-6f868bf2b452" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_299fe210-68a7-4802-b546-7911470facdc" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostTable_60fc7fc5-7c43-4f52-8f43-c48ddf78847a" xlink:to="loc_srt_StatementGeographicalAxis_299fe210-68a7-4802-b546-7911470facdc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_299fe210-68a7-4802-b546-7911470facdc_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_299fe210-68a7-4802-b546-7911470facdc" xlink:to="loc_srt_SegmentGeographicalDomain_299fe210-68a7-4802-b546-7911470facdc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_1a6bfc9e-04c4-49bd-ab40-d6534fca0204" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_299fe210-68a7-4802-b546-7911470facdc" xlink:to="loc_srt_SegmentGeographicalDomain_1a6bfc9e-04c4-49bd-ab40-d6534fca0204" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_7210574f-c2fd-404d-ab4c-4e5a005f9c15" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_1a6bfc9e-04c4-49bd-ab40-d6534fca0204" xlink:to="loc_srt_AmericasMember_7210574f-c2fd-404d-ab4c-4e5a005f9c15" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_c9e82027-a364-44e3-b823-3489f1232016" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_1a6bfc9e-04c4-49bd-ab40-d6534fca0204" xlink:to="loc_country_CA_c9e82027-a364-44e3-b823-3489f1232016" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_d020c18f-5015-483b-8917-3ee983998324" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_1a6bfc9e-04c4-49bd-ab40-d6534fca0204" xlink:to="loc_us-gaap_EMEAMember_d020c18f-5015-483b-8917-3ee983998324" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_6489ea5a-6341-41c8-ad70-1626f9f68c6f" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_1a6bfc9e-04c4-49bd-ab40-d6534fca0204" xlink:to="loc_srt_AsiaPacificMember_6489ea5a-6341-41c8-ad70-1626f9f68c6f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_1b9487ed-92ce-4df4-99b8-5be86795e757" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostTable_60fc7fc5-7c43-4f52-8f43-c48ddf78847a" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_1b9487ed-92ce-4df4-99b8-5be86795e757" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_1b9487ed-92ce-4df4-99b8-5be86795e757_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_1b9487ed-92ce-4df4-99b8-5be86795e757" xlink:to="loc_us-gaap_SegmentDomain_1b9487ed-92ce-4df4-99b8-5be86795e757_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_5b7c988f-e9c0-4487-adf4-bdf1002cb891" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_1b9487ed-92ce-4df4-99b8-5be86795e757" xlink:to="loc_us-gaap_SegmentDomain_5b7c988f-e9c0-4487-adf4-bdf1002cb891" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_900febbd-009a-4545-b413-ea9b33c06881" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_5b7c988f-e9c0-4487-adf4-bdf1002cb891" xlink:to="loc_us-gaap_AllOtherSegmentsMember_900febbd-009a-4545-b413-ea9b33c06881" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_648d82cf-95fc-475f-b0ae-fcf068706da7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_5b7c988f-e9c0-4487-adf4-bdf1002cb891" xlink:to="loc_us-gaap_CorporateAndOtherMember_648d82cf-95fc-475f-b0ae-fcf068706da7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_5f8d25ba-d800-4fed-a917-7eade2b076a3" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostTable_60fc7fc5-7c43-4f52-8f43-c48ddf78847a" xlink:to="loc_srt_MajorCustomersAxis_5f8d25ba-d800-4fed-a917-7eade2b076a3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_5f8d25ba-d800-4fed-a917-7eade2b076a3_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_5f8d25ba-d800-4fed-a917-7eade2b076a3" xlink:to="loc_srt_NameOfMajorCustomerDomain_5f8d25ba-d800-4fed-a917-7eade2b076a3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_fd33b2b8-4ab0-4241-a651-51363014776a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_5f8d25ba-d800-4fed-a917-7eade2b076a3" xlink:to="loc_srt_NameOfMajorCustomerDomain_fd33b2b8-4ab0-4241-a651-51363014776a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCosts_6e393bab-cc4b-4368-a1fe-3963b951feb6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredPolicyAcquisitionCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostLineItems_0c6e9923-2846-4252-9556-1f1d8e8f199f" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCosts_6e393bab-cc4b-4368-a1fe-3963b951feb6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostsAdditions_a67550a2-1e08-4cb0-ac6b-6ca3c5c0705b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredPolicyAcquisitionCostsAdditions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostLineItems_0c6e9923-2846-4252-9556-1f1d8e8f199f" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostsAdditions_a67550a2-1e08-4cb0-ac6b-6ca3c5c0705b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense_691375fa-5b65-4e5b-90dc-8f1d641a30d9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostLineItems_0c6e9923-2846-4252-9556-1f1d8e8f199f" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense_691375fa-5b65-4e5b-90dc-8f1d641a30d9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostForeignCurrencyTranslationGainLoss_2a79214e-05c1-44d3-be85-7c71ec275266" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DeferredPolicyAcquisitionCostForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostLineItems_0c6e9923-2846-4252-9556-1f1d8e8f199f" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostForeignCurrencyTranslationGainLoss_2a79214e-05c1-44d3-be85-7c71ec275266" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/ReinsuranceCededReinsuranceReceivableAssetsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#ReinsuranceCededReinsuranceReceivableAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/ReinsuranceCededReinsuranceReceivableAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskLineItems_cbf59685-5cd7-4b8d-8cb1-78fe7f1e92e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CededCreditRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskTable_a43c0cab-2ba2-410e-a435-34cff2b78f4a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CededCreditRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CededCreditRiskLineItems_cbf59685-5cd7-4b8d-8cb1-78fe7f1e92e2" xlink:to="loc_us-gaap_CededCreditRiskTable_a43c0cab-2ba2-410e-a435-34cff2b78f4a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestAxis_c303e638-f7e8-4e48-ac22-a7958524271e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CreditRatingAMBestAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_a43c0cab-2ba2-410e-a435-34cff2b78f4a" xlink:to="loc_srt_CreditRatingAMBestAxis_c303e638-f7e8-4e48-ac22-a7958524271e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestDomain_c303e638-f7e8-4e48-ac22-a7958524271e_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CreditRatingAMBestDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CreditRatingAMBestAxis_c303e638-f7e8-4e48-ac22-a7958524271e" xlink:to="loc_srt_CreditRatingAMBestDomain_c303e638-f7e8-4e48-ac22-a7958524271e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestDomain_3665cba8-bbc5-4283-8927-096172343a35" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CreditRatingAMBestDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CreditRatingAMBestAxis_c303e638-f7e8-4e48-ac22-a7958524271e" xlink:to="loc_srt_CreditRatingAMBestDomain_3665cba8-bbc5-4283-8927-096172343a35" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskAxis_04472b5a-b4fc-4415-8cdf-a1d1c3effcf0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CededCreditRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_a43c0cab-2ba2-410e-a435-34cff2b78f4a" xlink:to="loc_us-gaap_CededCreditRiskAxis_04472b5a-b4fc-4415-8cdf-a1d1c3effcf0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskReinsurerDomain_04472b5a-b4fc-4415-8cdf-a1d1c3effcf0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CededCreditRiskReinsurerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CededCreditRiskAxis_04472b5a-b4fc-4415-8cdf-a1d1c3effcf0" xlink:to="loc_us-gaap_CededCreditRiskReinsurerDomain_04472b5a-b4fc-4415-8cdf-a1d1c3effcf0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskReinsurerDomain_ee6faa1e-ffac-4787-80bd-eda81a3e747c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CededCreditRiskReinsurerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CededCreditRiskAxis_04472b5a-b4fc-4415-8cdf-a1d1c3effcf0" xlink:to="loc_us-gaap_CededCreditRiskReinsurerDomain_ee6faa1e-ffac-4787-80bd-eda81a3e747c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ReinsurerAMember_260b2b86-9de1-413f-9bc3-e6e3faf9a60d" xlink:href="rga-20240630.xsd#rga_ReinsurerAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskReinsurerDomain_ee6faa1e-ffac-4787-80bd-eda81a3e747c" xlink:to="loc_rga_ReinsurerAMember_260b2b86-9de1-413f-9bc3-e6e3faf9a60d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_a9d840e3-517e-4bca-9364-8b9f88728ff9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_a43c0cab-2ba2-410e-a435-34cff2b78f4a" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_a9d840e3-517e-4bca-9364-8b9f88728ff9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_a9d840e3-517e-4bca-9364-8b9f88728ff9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_a9d840e3-517e-4bca-9364-8b9f88728ff9" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_a9d840e3-517e-4bca-9364-8b9f88728ff9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_6fac170d-5570-4b84-980c-78831719e502" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_a9d840e3-517e-4bca-9364-8b9f88728ff9" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_6fac170d-5570-4b84-980c-78831719e502" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceRecoverables_2d426a7e-ceac-4d0d-93fe-da5ed9efbd85" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReinsuranceRecoverables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_cbf59685-5cd7-4b8d-8cb1-78fe7f1e92e2" xlink:to="loc_us-gaap_ReinsuranceRecoverables_2d426a7e-ceac-4d0d-93fe-da5ed9efbd85" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ReinsuranceCededReceivablesPercentageTotal_69f8c522-a470-4951-8a4a-fdb36f128e08" xlink:href="rga-20240630.xsd#rga_ReinsuranceCededReceivablesPercentageTotal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_cbf59685-5cd7-4b8d-8cb1-78fe7f1e92e2" xlink:to="loc_rga_ReinsuranceCededReceivablesPercentageTotal_69f8c522-a470-4951-8a4a-fdb36f128e08" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/ReinsuranceFundsWithheldDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#ReinsuranceFundsWithheldDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/ReinsuranceFundsWithheldDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_rga_ReinsuranceFundsWithheldAssetsLineItems_19b6c95c-b40c-485c-bb60-d707af0e81e2" xlink:href="rga-20240630.xsd#rga_ReinsuranceFundsWithheldAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ReinsuranceFundsWithheldAssetsTable_275063ff-a989-445a-b3f2-14555e01a969" xlink:href="rga-20240630.xsd#rga_ReinsuranceFundsWithheldAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_rga_ReinsuranceFundsWithheldAssetsLineItems_19b6c95c-b40c-485c-bb60-d707af0e81e2" xlink:to="loc_rga_ReinsuranceFundsWithheldAssetsTable_275063ff-a989-445a-b3f2-14555e01a969" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MajorCategoryOfInvestmentsAxis_5cc792e5-79ff-4c79-8ab6-8dbcb1ddf735" xlink:href="rga-20240630.xsd#rga_MajorCategoryOfInvestmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_ReinsuranceFundsWithheldAssetsTable_275063ff-a989-445a-b3f2-14555e01a969" xlink:to="loc_rga_MajorCategoryOfInvestmentsAxis_5cc792e5-79ff-4c79-8ab6-8dbcb1ddf735" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MajorCategoryOfInvestmentsDomain_5cc792e5-79ff-4c79-8ab6-8dbcb1ddf735_default" xlink:href="rga-20240630.xsd#rga_MajorCategoryOfInvestmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_MajorCategoryOfInvestmentsAxis_5cc792e5-79ff-4c79-8ab6-8dbcb1ddf735" xlink:to="loc_rga_MajorCategoryOfInvestmentsDomain_5cc792e5-79ff-4c79-8ab6-8dbcb1ddf735_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:href="rga-20240630.xsd#rga_MajorCategoryOfInvestmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_MajorCategoryOfInvestmentsAxis_5cc792e5-79ff-4c79-8ab6-8dbcb1ddf735" xlink:to="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FixedMaturitiesMember_fcc294ae-77e3-437f-b888-2a177dc3bc68" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FixedMaturitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_us-gaap_FixedMaturitiesMember_fcc294ae-77e3-437f-b888-2a177dc3bc68" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_1b85b5d1-c23d-408b-8b13-ce17cd67c912" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_us-gaap_EquitySecuritiesMember_1b85b5d1-c23d-408b-8b13-ce17cd67c912" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgagesMember_7b1bb02f-5503-47f5-9ed7-93c3a7fe7fea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MortgagesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_us-gaap_MortgagesMember_7b1bb02f-5503-47f5-9ed7-93c3a7fe7fea" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FundsWithheldAtInterestMember_342f1d2e-6a1b-4fd6-9401-865ad9d771f2" xlink:href="rga-20240630.xsd#rga_FundsWithheldAtInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_rga_FundsWithheldAtInterestMember_342f1d2e-6a1b-4fd6-9401-865ad9d771f2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PartnershipMember_12546d55-f4ef-4042-a500-2393c8157f7c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PartnershipMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_us-gaap_PartnershipMember_12546d55-f4ef-4042-a500-2393c8157f7c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestmentsMember_5e0355ec-a835-4979-9e20-36953313d0db" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortTermInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_us-gaap_ShortTermInvestmentsMember_5e0355ec-a835-4979-9e20-36953313d0db" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedIncomeReceivableMember_ced6ace0-7057-4c0d-8e3f-72f5c17cd026" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccruedIncomeReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_us-gaap_AccruedIncomeReceivableMember_ced6ace0-7057-4c0d-8e3f-72f5c17cd026" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsMember_428bfbc6-fa27-447f-b78d-3e55fa566347" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_us-gaap_OtherAssetsMember_428bfbc6-fa27-447f-b78d-3e55fa566347" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsMember_cbeeea09-603f-4b11-92b1-3e78da84ac4b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoryOfInvestmentsDomain_29c42900-8875-4fe5-b828-fe4a47f8cf6e" xlink:to="loc_us-gaap_AssetsMember_cbeeea09-603f-4b11-92b1-3e78da84ac4b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsAsset_63ec8ad8-4753-494b-9d34-877903855294" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FundsHeldUnderReinsuranceAgreementsAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_ReinsuranceFundsWithheldAssetsLineItems_19b6c95c-b40c-485c-bb60-d707af0e81e2" xlink:to="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsAsset_63ec8ad8-4753-494b-9d34-877903855294" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/ReinsuranceNarrativeDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#ReinsuranceNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/ReinsuranceNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskLineItems_4b0c5935-6e95-4d11-8194-066aa6742dd9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CededCreditRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskTable_9d26c34e-b7a2-4df7-bead-406f8bceff12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CededCreditRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CededCreditRiskLineItems_4b0c5935-6e95-4d11-8194-066aa6742dd9" xlink:to="loc_us-gaap_CededCreditRiskTable_9d26c34e-b7a2-4df7-bead-406f8bceff12" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestAxis_f46d2610-c2e6-45d6-85bc-da57c91a9681" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CreditRatingAMBestAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_9d26c34e-b7a2-4df7-bead-406f8bceff12" xlink:to="loc_srt_CreditRatingAMBestAxis_f46d2610-c2e6-45d6-85bc-da57c91a9681" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestDomain_f46d2610-c2e6-45d6-85bc-da57c91a9681_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CreditRatingAMBestDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CreditRatingAMBestAxis_f46d2610-c2e6-45d6-85bc-da57c91a9681" xlink:to="loc_srt_CreditRatingAMBestDomain_f46d2610-c2e6-45d6-85bc-da57c91a9681_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestDomain_33edebcf-c28d-4081-81d9-382bcebf0199" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CreditRatingAMBestDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CreditRatingAMBestAxis_f46d2610-c2e6-45d6-85bc-da57c91a9681" xlink:to="loc_srt_CreditRatingAMBestDomain_33edebcf-c28d-4081-81d9-382bcebf0199" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AMBestBPlusPlusRatingMember_18416a63-4faf-4b70-ab37-b08174c4c576" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AMBestBPlusPlusRatingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CreditRatingAMBestDomain_33edebcf-c28d-4081-81d9-382bcebf0199" xlink:to="loc_srt_AMBestBPlusPlusRatingMember_18416a63-4faf-4b70-ab37-b08174c4c576" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskCreditRiskReinsurance_796cc18e-0b27-4503-ad44-707dfb7bb642" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConcentrationRiskCreditRiskReinsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_4b0c5935-6e95-4d11-8194-066aa6742dd9" xlink:to="loc_us-gaap_ConcentrationRiskCreditRiskReinsurance_796cc18e-0b27-4503-ad44-707dfb7bb642" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ClaimsRecoverableFromRetrocessionairesPastDue_cb3ebc4a-8477-4b6c-a679-8d1b39c7041e" xlink:href="rga-20240630.xsd#rga_ClaimsRecoverableFromRetrocessionairesPastDue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_4b0c5935-6e95-4d11-8194-066aa6742dd9" xlink:to="loc_rga_ClaimsRecoverableFromRetrocessionairesPastDue_cb3ebc4a-8477-4b6c-a679-8d1b39c7041e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeAsset_09cb1b20-b950-4b05-b4cb-b2db2fe50e12" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_4b0c5935-6e95-4d11-8194-066aa6742dd9" xlink:to="loc_us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeAsset_09cb1b20-b950-4b05-b4cb-b2db2fe50e12" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsLiability_3908ce4c-a626-432f-96e1-c7b9f32c8c6f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FundsHeldUnderReinsuranceAgreementsLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_4b0c5935-6e95-4d11-8194-066aa6742dd9" xlink:to="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsLiability_3908ce4c-a626-432f-96e1-c7b9f32c8c6f" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsInvestmentsinFixedMaturityandEquitySecuritiesAvailableforSalebySectorDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsInvestmentsinFixedMaturityandEquitySecuritiesAvailableforSalebySectorDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsInvestmentsinFixedMaturityandEquitySecuritiesAvailableforSalebySectorDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_bdec7ab2-d659-4c79-b569-a8c490c5c75d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_bc89c185-1056-4f80-9ccb-3dc01602a407" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_bdec7ab2-d659-4c79-b569-a8c490c5c75d" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_bc89c185-1056-4f80-9ccb-3dc01602a407" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_801328a6-bd57-4bd9-864d-b3efe38ced81" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_bc89c185-1056-4f80-9ccb-3dc01602a407" xlink:to="loc_us-gaap_FinancialInstrumentAxis_801328a6-bd57-4bd9-864d-b3efe38ced81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_801328a6-bd57-4bd9-864d-b3efe38ced81_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_801328a6-bd57-4bd9-864d-b3efe38ced81" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_801328a6-bd57-4bd9-864d-b3efe38ced81_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_801328a6-bd57-4bd9-864d-b3efe38ced81" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_ab3adccd-f505-40fc-b722-ca8077057bc7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_ab3adccd-f505-40fc-b722-ca8077057bc7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CanadianProvincialGovernmentsMember_c35cc0f5-4242-4c34-a5c7-2a32a0e12715" xlink:href="rga-20240630.xsd#rga_CanadianProvincialGovernmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_rga_CanadianProvincialGovernmentsMember_c35cc0f5-4242-4c34-a5c7-2a32a0e12715" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_ed9a8af3-7159-4313-98d7-320cf828c268" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_ed9a8af3-7159-4313-98d7-320cf828c268" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_34acedb4-a5ea-44ac-9272-38a5f0fe6801" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_34acedb4-a5ea-44ac-9272-38a5f0fe6801" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_74f63ecb-1311-43db-8147-a51cfac86516" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_74f63ecb-1311-43db-8147-a51cfac86516" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_562519a4-4dbc-4b38-959d-799b7ea1de36" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_562519a4-4dbc-4b38-959d-799b7ea1de36" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_53298f7c-280e-40e1-b493-66367bd95e60" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_53298f7c-280e-40e1-b493-66367bd95e60" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_f23da467-bfcd-4924-9114-a6c21d117641" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_f23da467-bfcd-4924-9114-a6c21d117641" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_JP_67ecc492-1f78-45ac-ac26-925fe7ae6919" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_JP"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_30e0c2f4-db60-4448-a005-d8aacf16e39b" xlink:to="loc_country_JP_67ecc492-1f78-45ac-ac26-925fe7ae6919" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_7fb2b9e9-c60c-4534-94bc-ae1b4a262c0f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_bc89c185-1056-4f80-9ccb-3dc01602a407" xlink:to="loc_us-gaap_InvestmentTypeAxis_7fb2b9e9-c60c-4534-94bc-ae1b4a262c0f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_7fb2b9e9-c60c-4534-94bc-ae1b4a262c0f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_7fb2b9e9-c60c-4534-94bc-ae1b4a262c0f" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_7fb2b9e9-c60c-4534-94bc-ae1b4a262c0f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_68243ef0-a031-475d-b1ed-81e6620ae5d8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_7fb2b9e9-c60c-4534-94bc-ae1b4a262c0f" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_68243ef0-a031-475d-b1ed-81e6620ae5d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_524a7697-538b-4ec3-bd79-b79f71b41cab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_bdec7ab2-d659-4c79-b569-a8c490c5c75d" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_524a7697-538b-4ec3-bd79-b79f71b41cab" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_656918d1-6a1a-48dd-b7ae-aadcd8272356" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_bdec7ab2-d659-4c79-b569-a8c490c5c75d" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_656918d1-6a1a-48dd-b7ae-aadcd8272356" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_28ed3ca9-71a5-452f-a230-abe9a7df19cf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_bdec7ab2-d659-4c79-b569-a8c490c5c75d" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_28ed3ca9-71a5-452f-a230-abe9a7df19cf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_82a40ea6-d5c4-454d-95e6-f9ddee915ed5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_bdec7ab2-d659-4c79-b569-a8c490c5c75d" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_82a40ea6-d5c4-454d-95e6-f9ddee915ed5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PercentageOfTotalAvailableForSaleSecurities_aeb77559-32ba-425a-92d4-2ca4b31a15ad" xlink:href="rga-20240630.xsd#rga_PercentageOfTotalAvailableForSaleSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_bdec7ab2-d659-4c79-b569-a8c490c5c75d" xlink:to="loc_rga_PercentageOfTotalAvailableForSaleSecurities_aeb77559-32ba-425a-92d4-2ca4b31a15ad" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_79e97770-814e-410a-abde-cc4c5825e502" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_bdec7ab2-d659-4c79-b569-a8c490c5c75d" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_79e97770-814e-410a-abde-cc4c5825e502" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsFixedMaturitySecuritiesPledgedAndReceivedAsCollateralDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsFixedMaturitySecuritiesPledgedAndReceivedAsCollateralDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsFixedMaturitySecuritiesPledgedAndReceivedAsCollateralDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_8213673f-4743-4b9d-aa05-12f1d74f7161" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4edf6954-f5d9-4d34-852f-1768a9e326b4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_8213673f-4743-4b9d-aa05-12f1d74f7161" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4edf6954-f5d9-4d34-852f-1768a9e326b4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AvailableForSaleSecuritiesAxis_b03b8980-1289-432e-a1e2-069d60d828d5" xlink:href="rga-20240630.xsd#rga_AvailableForSaleSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4edf6954-f5d9-4d34-852f-1768a9e326b4" xlink:to="loc_rga_AvailableForSaleSecuritiesAxis_b03b8980-1289-432e-a1e2-069d60d828d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AvailableForSaleSecuritiesDomain_b03b8980-1289-432e-a1e2-069d60d828d5_default" xlink:href="rga-20240630.xsd#rga_AvailableForSaleSecuritiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_AvailableForSaleSecuritiesAxis_b03b8980-1289-432e-a1e2-069d60d828d5" xlink:to="loc_rga_AvailableForSaleSecuritiesDomain_b03b8980-1289-432e-a1e2-069d60d828d5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AvailableForSaleSecuritiesDomain_13acc262-5a75-408b-a5c0-0253931fd460" xlink:href="rga-20240630.xsd#rga_AvailableForSaleSecuritiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_AvailableForSaleSecuritiesAxis_b03b8980-1289-432e-a1e2-069d60d828d5" xlink:to="loc_rga_AvailableForSaleSecuritiesDomain_13acc262-5a75-408b-a5c0-0253931fd460" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CollateralFixedMaturitySecuritiesMember_4dc98fd6-83ed-4eaf-ae56-99757470d67b" xlink:href="rga-20240630.xsd#rga_CollateralFixedMaturitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AvailableForSaleSecuritiesDomain_13acc262-5a75-408b-a5c0-0253931fd460" xlink:to="loc_rga_CollateralFixedMaturitySecuritiesMember_4dc98fd6-83ed-4eaf-ae56-99757470d67b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CollateralReceivedFixedMaturitySecuritiesMember_6561a796-a6f4-44ef-8bf9-0953393b7346" xlink:href="rga-20240630.xsd#rga_CollateralReceivedFixedMaturitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AvailableForSaleSecuritiesDomain_13acc262-5a75-408b-a5c0-0253931fd460" xlink:to="loc_rga_CollateralReceivedFixedMaturitySecuritiesMember_6561a796-a6f4-44ef-8bf9-0953393b7346" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_5ba39e6e-8cf5-4329-a934-097ddde0f21a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AvailableForSaleSecuritiesDomain_13acc262-5a75-408b-a5c0-0253931fd460" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_5ba39e6e-8cf5-4329-a934-097ddde0f21a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_dce34ab7-0144-4f43-bd21-305b7e681b86" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AvailableForSaleSecuritiesDomain_13acc262-5a75-408b-a5c0-0253931fd460" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_dce34ab7-0144-4f43-bd21-305b7e681b86" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_7ce804db-5fe2-4bef-8742-ed83ea61ab26" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AvailableForSaleSecuritiesDomain_13acc262-5a75-408b-a5c0-0253931fd460" xlink:to="loc_us-gaap_DepositsMember_7ce804db-5fe2-4bef-8742-ed83ea61ab26" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankCertificatesAndObligationsFHLBMember_ae4e5fd5-75cf-4593-a571-8029d16e154f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FederalHomeLoanBankCertificatesAndObligationsFHLBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AvailableForSaleSecuritiesDomain_13acc262-5a75-408b-a5c0-0253931fd460" xlink:to="loc_us-gaap_FederalHomeLoanBankCertificatesAndObligationsFHLBMember_ae4e5fd5-75cf-4593-a571-8029d16e154f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_6fcc25e7-ee1c-4adb-8ef0-259e54850671" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_8213673f-4743-4b9d-aa05-12f1d74f7161" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_6fcc25e7-ee1c-4adb-8ef0-259e54850671" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_418bb47f-c3c3-4ae0-a404-a313ec71c212" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_8213673f-4743-4b9d-aa05-12f1d74f7161" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_418bb47f-c3c3-4ae0-a404-a313ec71c212" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldInTrust_b9f072eb-31cd-44bd-9dbc-d9b476d0d173" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsHeldInTrust"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_8213673f-4743-4b9d-aa05-12f1d74f7161" xlink:to="loc_us-gaap_AssetsHeldInTrust_b9f072eb-31cd-44bd-9dbc-d9b476d0d173" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsExposureToConcentrationsOfCreditRiskDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsExposureToConcentrationsOfCreditRiskDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsExposureToConcentrationsOfCreditRiskDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_e461605d-c1a9-4f7d-b580-c040712f1ef1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4dc87a31-ad55-4635-9f8e-590ad7d1e20b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_e461605d-c1a9-4f7d-b580-c040712f1ef1" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4dc87a31-ad55-4635-9f8e-590ad7d1e20b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AvailableForSaleSecuritiesAxis_059ff35e-66f7-4cb1-b9a9-5de3d1a82fc7" xlink:href="rga-20240630.xsd#rga_AvailableForSaleSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4dc87a31-ad55-4635-9f8e-590ad7d1e20b" xlink:to="loc_rga_AvailableForSaleSecuritiesAxis_059ff35e-66f7-4cb1-b9a9-5de3d1a82fc7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AvailableForSaleSecuritiesDomain_059ff35e-66f7-4cb1-b9a9-5de3d1a82fc7_default" xlink:href="rga-20240630.xsd#rga_AvailableForSaleSecuritiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_AvailableForSaleSecuritiesAxis_059ff35e-66f7-4cb1-b9a9-5de3d1a82fc7" xlink:to="loc_rga_AvailableForSaleSecuritiesDomain_059ff35e-66f7-4cb1-b9a9-5de3d1a82fc7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AvailableForSaleSecuritiesDomain_62c33b2d-5f77-499e-bc93-b9f12e00a7d4" xlink:href="rga-20240630.xsd#rga_AvailableForSaleSecuritiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_AvailableForSaleSecuritiesAxis_059ff35e-66f7-4cb1-b9a9-5de3d1a82fc7" xlink:to="loc_rga_AvailableForSaleSecuritiesDomain_62c33b2d-5f77-499e-bc93-b9f12e00a7d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CanadianProvinceOfQuebecSecuritiesMember_20fbf244-a7fe-496b-ae96-caf818a2b152" xlink:href="rga-20240630.xsd#rga_CanadianProvinceOfQuebecSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AvailableForSaleSecuritiesDomain_62c33b2d-5f77-499e-bc93-b9f12e00a7d4" xlink:to="loc_rga_CanadianProvinceOfQuebecSecuritiesMember_20fbf244-a7fe-496b-ae96-caf818a2b152" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CanadianProvinceOfOntarioSecuritiesMember_1028d1c7-648d-4397-a89c-4fb3f7ff0c73" xlink:href="rga-20240630.xsd#rga_CanadianProvinceOfOntarioSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_AvailableForSaleSecuritiesDomain_62c33b2d-5f77-499e-bc93-b9f12e00a7d4" xlink:to="loc_rga_CanadianProvinceOfOntarioSecuritiesMember_1028d1c7-648d-4397-a89c-4fb3f7ff0c73" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_7c8f520f-4267-46c0-bdb3-4aff28734c40" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_4dc87a31-ad55-4635-9f8e-590ad7d1e20b" xlink:to="loc_us-gaap_FinancialInstrumentAxis_7c8f520f-4267-46c0-bdb3-4aff28734c40" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7c8f520f-4267-46c0-bdb3-4aff28734c40_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_7c8f520f-4267-46c0-bdb3-4aff28734c40" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7c8f520f-4267-46c0-bdb3-4aff28734c40_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_c5a64534-d819-44e2-af95-6b53c541a5b7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_7c8f520f-4267-46c0-bdb3-4aff28734c40" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_c5a64534-d819-44e2-af95-6b53c541a5b7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_JP_69332607-5b6c-4b19-9a61-f95f9d39165a" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_JP"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_c5a64534-d819-44e2-af95-6b53c541a5b7" xlink:to="loc_country_JP_69332607-5b6c-4b19-9a61-f95f9d39165a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_50430996-ce4b-437d-bb38-5d7f421354eb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_c5a64534-d819-44e2-af95-6b53c541a5b7" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_50430996-ce4b-437d-bb38-5d7f421354eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_ccff657f-8dbc-4355-a346-3a763ee265e2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_e461605d-c1a9-4f7d-b580-c040712f1ef1" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_ccff657f-8dbc-4355-a346-3a763ee265e2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_6c783adb-d2dd-4aae-9a00-166fc1b5176b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_e461605d-c1a9-4f7d-b580-c040712f1ef1" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_6c783adb-d2dd-4aae-9a00-166fc1b5176b" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsAmortizedCostandFairValueofFixedMaturityHoldingsbyIndustryTypeDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsAmortizedCostandFairValueofFixedMaturityHoldingsbyIndustryTypeDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsAmortizedCostandFairValueofFixedMaturityHoldingsbyIndustryTypeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_rga_CorporateSecuritiesByInvestmentSectorAndCreditRatingLineItems_9a5f88ca-2c18-4611-9b23-6cc91d451d5d" xlink:href="rga-20240630.xsd#rga_CorporateSecuritiesByInvestmentSectorAndCreditRatingLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ScheduleOfCorporateSecuritiesByMajorIndustryAndCreditRatingTable_0aa7eec2-0404-4e0d-a333-d630f7af4980" xlink:href="rga-20240630.xsd#rga_ScheduleOfCorporateSecuritiesByMajorIndustryAndCreditRatingTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_rga_CorporateSecuritiesByInvestmentSectorAndCreditRatingLineItems_9a5f88ca-2c18-4611-9b23-6cc91d451d5d" xlink:to="loc_rga_ScheduleOfCorporateSecuritiesByMajorIndustryAndCreditRatingTable_0aa7eec2-0404-4e0d-a333-d630f7af4980" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_eb8800a8-8b4e-4faf-b4b5-006b576e6d33" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_ScheduleOfCorporateSecuritiesByMajorIndustryAndCreditRatingTable_0aa7eec2-0404-4e0d-a333-d630f7af4980" xlink:to="loc_us-gaap_FinancialInstrumentAxis_eb8800a8-8b4e-4faf-b4b5-006b576e6d33" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_eb8800a8-8b4e-4faf-b4b5-006b576e6d33_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_eb8800a8-8b4e-4faf-b4b5-006b576e6d33" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_eb8800a8-8b4e-4faf-b4b5-006b576e6d33_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_06e735cd-9c4e-4f63-9f2c-e9f1dd5cd0c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_eb8800a8-8b4e-4faf-b4b5-006b576e6d33" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_06e735cd-9c4e-4f63-9f2c-e9f1dd5cd0c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_025a0dde-6870-4018-a857-fabfa76f55e1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_06e735cd-9c4e-4f63-9f2c-e9f1dd5cd0c9" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_025a0dde-6870-4018-a857-fabfa76f55e1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesByIndustryAxis_f5e13110-8918-488b-a8a2-ea9e19ce5ea3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquitySecuritiesByIndustryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_ScheduleOfCorporateSecuritiesByMajorIndustryAndCreditRatingTable_0aa7eec2-0404-4e0d-a333-d630f7af4980" xlink:to="loc_us-gaap_EquitySecuritiesByIndustryAxis_f5e13110-8918-488b-a8a2-ea9e19ce5ea3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesIndustryMember_f5e13110-8918-488b-a8a2-ea9e19ce5ea3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquitySecuritiesIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EquitySecuritiesByIndustryAxis_f5e13110-8918-488b-a8a2-ea9e19ce5ea3" xlink:to="loc_us-gaap_EquitySecuritiesIndustryMember_f5e13110-8918-488b-a8a2-ea9e19ce5ea3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesIndustryMember_bf637fe6-f290-421c-adf3-bcda61a855d0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquitySecuritiesIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EquitySecuritiesByIndustryAxis_f5e13110-8918-488b-a8a2-ea9e19ce5ea3" xlink:to="loc_us-gaap_EquitySecuritiesIndustryMember_bf637fe6-f290-421c-adf3-bcda61a855d0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FinanceIndustryMember_212c0117-e2f6-4499-b197-167f02ff36b7" xlink:href="rga-20240630.xsd#rga_FinanceIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_bf637fe6-f290-421c-adf3-bcda61a855d0" xlink:to="loc_rga_FinanceIndustryMember_212c0117-e2f6-4499-b197-167f02ff36b7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_IndustrialMember_3e72a049-6aa5-40bb-9e54-10f1c7013c4f" xlink:href="rga-20240630.xsd#rga_IndustrialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_bf637fe6-f290-421c-adf3-bcda61a855d0" xlink:to="loc_rga_IndustrialMember_3e72a049-6aa5-40bb-9e54-10f1c7013c4f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_UtilityIndustryMember_c7686f32-6328-4640-9a0a-5781a93d5c1a" xlink:href="rga-20240630.xsd#rga_UtilityIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_bf637fe6-f290-421c-adf3-bcda61a855d0" xlink:to="loc_rga_UtilityIndustryMember_c7686f32-6328-4640-9a0a-5781a93d5c1a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_69f1d704-b37f-431c-86a0-7ae124abec3d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_CorporateSecuritiesByInvestmentSectorAndCreditRatingLineItems_9a5f88ca-2c18-4611-9b23-6cc91d451d5d" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_69f1d704-b37f-431c-86a0-7ae124abec3d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_f7dda8b6-702d-4b69-b85c-8b266d3db5d8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_CorporateSecuritiesByInvestmentSectorAndCreditRatingLineItems_9a5f88ca-2c18-4611-9b23-6cc91d451d5d" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_f7dda8b6-702d-4b69-b85c-8b266d3db5d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PercentageOfTotalAvailableForSaleSecurities_3bd15307-62db-4102-8df7-8726fbd3bc6c" xlink:href="rga-20240630.xsd#rga_PercentageOfTotalAvailableForSaleSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_CorporateSecuritiesByInvestmentSectorAndCreditRatingLineItems_9a5f88ca-2c18-4611-9b23-6cc91d451d5d" xlink:to="loc_rga_PercentageOfTotalAvailableForSaleSecurities_3bd15307-62db-4102-8df7-8726fbd3bc6c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_PercentageOfTotalCorporateFixedMaturitySecurity_1da128b5-286c-4a56-a782-be7085def520" xlink:href="rga-20240630.xsd#rga_PercentageOfTotalCorporateFixedMaturitySecurity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_CorporateSecuritiesByInvestmentSectorAndCreditRatingLineItems_9a5f88ca-2c18-4611-9b23-6cc91d451d5d" xlink:to="loc_rga_PercentageOfTotalCorporateFixedMaturitySecurity_1da128b5-286c-4a56-a782-be7085def520" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsInvestmentsAllowanceforCreditLossRollForwardDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsInvestmentsAllowanceforCreditLossRollForwardDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsInvestmentsAllowanceforCreditLossRollForwardDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsLineItems_2696a0b2-c0e2-4686-ac11-a1a172971f99" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfOtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsTable_2de1148e-639a-485d-86e1-d0051263a088" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfOtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsLineItems_2696a0b2-c0e2-4686-ac11-a1a172971f99" xlink:to="loc_us-gaap_ScheduleOfOtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsTable_2de1148e-639a-485d-86e1-d0051263a088" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InformationByCategoryOfDebtSecurityAxis_a156e29c-f973-4b37-916d-69fd898a0e94" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InformationByCategoryOfDebtSecurityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfOtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsTable_2de1148e-639a-485d-86e1-d0051263a088" xlink:to="loc_us-gaap_InformationByCategoryOfDebtSecurityAxis_a156e29c-f973-4b37-916d-69fd898a0e94" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCategoriesOfInvestmentsDomain_a156e29c-f973-4b37-916d-69fd898a0e94_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCategoriesOfInvestmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InformationByCategoryOfDebtSecurityAxis_a156e29c-f973-4b37-916d-69fd898a0e94" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCategoriesOfInvestmentsDomain_a156e29c-f973-4b37-916d-69fd898a0e94_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCategoriesOfInvestmentsDomain_e4fec3cc-d3c3-4d6c-9b70-13bd46fc9755" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCategoriesOfInvestmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InformationByCategoryOfDebtSecurityAxis_a156e29c-f973-4b37-916d-69fd898a0e94" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCategoriesOfInvestmentsDomain_e4fec3cc-d3c3-4d6c-9b70-13bd46fc9755" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableforsaleSecuritiesMember_29b2184f-f50a-4ede-9884-390644352ded" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableforsaleSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCategoriesOfInvestmentsDomain_e4fec3cc-d3c3-4d6c-9b70-13bd46fc9755" xlink:to="loc_us-gaap_AvailableforsaleSecuritiesMember_29b2184f-f50a-4ede-9884-390644352ded" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_664f7741-8230-42a4-8268-aa43d9807989" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfOtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsTable_2de1148e-639a-485d-86e1-d0051263a088" xlink:to="loc_us-gaap_FinancialInstrumentAxis_664f7741-8230-42a4-8268-aa43d9807989" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_664f7741-8230-42a4-8268-aa43d9807989_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_664f7741-8230-42a4-8268-aa43d9807989" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_664f7741-8230-42a4-8268-aa43d9807989_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d4a5f15f-e7d4-4229-9ae4-8df1de255892" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_664f7741-8230-42a4-8268-aa43d9807989" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d4a5f15f-e7d4-4229-9ae4-8df1de255892" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_493e9dad-7cba-4a0c-89bc-ed7394bd236b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d4a5f15f-e7d4-4229-9ae4-8df1de255892" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_493e9dad-7cba-4a0c-89bc-ed7394bd236b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_fd81a0e4-92f5-443b-9b91-7d1a889be6af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d4a5f15f-e7d4-4229-9ae4-8df1de255892" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_fd81a0e4-92f5-443b-9b91-7d1a889be6af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_d51b8b5f-2826-49b7-8155-fd419c31c8fd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d4a5f15f-e7d4-4229-9ae4-8df1de255892" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_d51b8b5f-2826-49b7-8155-fd419c31c8fd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_bd2cc8a8-9a89-45dc-bc3f-13bcea50095e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_d4a5f15f-e7d4-4229-9ae4-8df1de255892" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_bd2cc8a8-9a89-45dc-bc3f-13bcea50095e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_11c2e82b-487c-446b-b595-ce1666faf1a7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsLineItems_2696a0b2-c0e2-4686-ac11-a1a172971f99" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_11c2e82b-487c-446b-b595-ce1666faf1a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld_f6c053a0-0ea7-4d59-aafb-42a6ec6c5ff7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_11c2e82b-487c-446b-b595-ce1666faf1a7" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld_f6c053a0-0ea7-4d59-aafb-42a6ec6c5ff7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment_dce44b9a-c62e-4d04-96cd-3cbc80e99d71" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_11c2e82b-487c-446b-b595-ce1666faf1a7" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment_dce44b9a-c62e-4d04-96cd-3cbc80e99d71" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold_d756af73-f8a4-4c6b-bb7e-692a3021108a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_11c2e82b-487c-446b-b595-ce1666faf1a7" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold_d756af73-f8a4-4c6b-bb7e-692a3021108a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease_d6ae2767-c867-4c69-b2fe-82ac7cc83be8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_11c2e82b-487c-446b-b595-ce1666faf1a7" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease_d6ae2767-c867-4c69-b2fe-82ac7cc83be8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsWriteOffs_f1e5db52-23d0-44e5-bdd1-752fc62f9485" xlink:href="rga-20240630.xsd#rga_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsWriteOffs"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForward_11c2e82b-487c-446b-b595-ce1666faf1a7" xlink:to="loc_rga_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsWriteOffs_f1e5db52-23d0-44e5-bdd1-752fc62f9485" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld_46a8a554-9408-4975-84e5-a0b0c5bdc116" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsFairValueandLossesbyInvestmentCategoryandLengthofTimeinaLossPositionDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsFairValueandLossesbyInvestmentCategoryandLengthofTimeinaLossPositionDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsFairValueandLossesbyInvestmentCategoryandLengthofTimeinaLossPositionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems_8af47f8c-7d61-4c05-a1fd-0b6eb3bd6ce4" xlink:href="rga-20240630.xsd#rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_ee8d3040-2564-42fa-a195-8aba86caa28a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems_8af47f8c-7d61-4c05-a1fd-0b6eb3bd6ce4" xlink:to="loc_us-gaap_StatementTable_ee8d3040-2564-42fa-a195-8aba86caa28a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_67df0f20-2866-410a-b933-053718f09b67" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_ee8d3040-2564-42fa-a195-8aba86caa28a" xlink:to="loc_us-gaap_FinancialInstrumentAxis_67df0f20-2866-410a-b933-053718f09b67" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_67df0f20-2866-410a-b933-053718f09b67_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_67df0f20-2866-410a-b933-053718f09b67" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_67df0f20-2866-410a-b933-053718f09b67_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_67df0f20-2866-410a-b933-053718f09b67" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_1c75685c-4648-42de-b8a6-561ea623fbbc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_1c75685c-4648-42de-b8a6-561ea623fbbc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CanadianProvincialGovernmentsMember_3841795c-a2a6-4a05-96bb-174e951a9e30" xlink:href="rga-20240630.xsd#rga_CanadianProvincialGovernmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_rga_CanadianProvincialGovernmentsMember_3841795c-a2a6-4a05-96bb-174e951a9e30" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_dbb00fc8-472f-48bf-8150-d351d2669813" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_dbb00fc8-472f-48bf-8150-d351d2669813" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_3b1f96eb-6b2b-4217-aa9e-de9346fe9daa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_3b1f96eb-6b2b-4217-aa9e-de9346fe9daa" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_fac96f96-1498-4bd2-bbe0-8b7943086fdc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_fac96f96-1498-4bd2-bbe0-8b7943086fdc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_7c508974-45bb-483d-8f16-47658a49bbcf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_7c508974-45bb-483d-8f16-47658a49bbcf" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_6de7a3d4-4a98-4a25-a197-2d973b9ea88a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_6de7a3d4-4a98-4a25-a197-2d973b9ea88a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_6f725cc3-a83f-4b50-854d-61a3b7e28f56" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_6f725cc3-a83f-4b50-854d-61a3b7e28f56" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_JP_9e34ddc4-7910-4815-b2e9-aa76dad5e658" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_JP"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_04aac95f-fa85-4fce-a525-939188578720" xlink:to="loc_country_JP_9e34ddc4-7910-4815-b2e9-aa76dad5e658" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingAxis_9b291560-cf0b-4617-8983-ba11d9e9f8fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingByGroupingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_ee8d3040-2564-42fa-a195-8aba86caa28a" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingAxis_9b291560-cf0b-4617-8983-ba11d9e9f8fc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingDomain_9b291560-cf0b-4617-8983-ba11d9e9f8fc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingByGroupingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingAxis_9b291560-cf0b-4617-8983-ba11d9e9f8fc" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingDomain_9b291560-cf0b-4617-8983-ba11d9e9f8fc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingDomain_3c880687-e8ee-46d4-89db-45a0246c3757" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingByGroupingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingAxis_9b291560-cf0b-4617-8983-ba11d9e9f8fc" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingDomain_3c880687-e8ee-46d4-89db-45a0246c3757" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingInvestmentGradeMember_11b42b4d-4492-4e53-874d-828abb4f9d2c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingDomain_3c880687-e8ee-46d4-89db-45a0246c3757" xlink:to="loc_us-gaap_ExternalCreditRatingInvestmentGradeMember_11b42b4d-4492-4e53-874d-828abb4f9d2c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingNonInvestmentGradeMember_3a25eeeb-b374-41e5-a0aa-0ff555ad4bbb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingNonInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingDomain_3c880687-e8ee-46d4-89db-45a0246c3757" xlink:to="loc_us-gaap_ExternalCreditRatingNonInvestmentGradeMember_3a25eeeb-b374-41e5-a0aa-0ff555ad4bbb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_ae7ec9b6-2f01-43dd-8c4d-b38787010bde" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_ee8d3040-2564-42fa-a195-8aba86caa28a" xlink:to="loc_us-gaap_InvestmentTypeAxis_ae7ec9b6-2f01-43dd-8c4d-b38787010bde" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_ae7ec9b6-2f01-43dd-8c4d-b38787010bde_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_ae7ec9b6-2f01-43dd-8c4d-b38787010bde" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_ae7ec9b6-2f01-43dd-8c4d-b38787010bde_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_85eddcb4-edeb-4b23-ba01-801e4f3c67a0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_ae7ec9b6-2f01-43dd-8c4d-b38787010bde" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_85eddcb4-edeb-4b23-ba01-801e4f3c67a0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_1bdec6eb-a95d-464b-a0f1-16ebdbb0ae63" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems_8af47f8c-7d61-4c05-a1fd-0b6eb3bd6ce4" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_1bdec6eb-a95d-464b-a0f1-16ebdbb0ae63" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_b7367af4-028b-43eb-b6c0-02583555d00c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems_8af47f8c-7d61-4c05-a1fd-0b6eb3bd6ce4" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_b7367af4-028b-43eb-b6c0-02583555d00c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_e2fada9a-c45e-4807-bc18-1e04e48b7fc2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems_8af47f8c-7d61-4c05-a1fd-0b6eb3bd6ce4" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_e2fada9a-c45e-4807-bc18-1e04e48b7fc2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_6a2bd928-0427-42f5-afe7-d0123f14aeb1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems_8af47f8c-7d61-4c05-a1fd-0b6eb3bd6ce4" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_6a2bd928-0427-42f5-afe7-d0123f14aeb1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_880d32e0-39fe-47a2-8554-56d0a899bfaf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems_8af47f8c-7d61-4c05-a1fd-0b6eb3bd6ce4" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_880d32e0-39fe-47a2-8554-56d0a899bfaf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_3875e864-afbe-4267-8a5e-e393f6344406" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_EstimatedFairValuesAndGrossUnrealizedLossesOttiImpairmentLossesReportedInAociLineItems_8af47f8c-7d61-4c05-a1fd-0b6eb3bd6ce4" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_3875e864-afbe-4267-8a5e-e393f6344406" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsInvestmentIncomeNetofRelatedExpensesDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsInvestmentIncomeNetofRelatedExpensesDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsInvestmentIncomeNetofRelatedExpensesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_rga_MajorCategoriesOfInvestmentIncomeNetOfExpensesLineItems_3746d0c2-0ad6-4d53-ae4e-2c9e2b3d6afb" xlink:href="rga-20240630.xsd#rga_MajorCategoriesOfInvestmentIncomeNetOfExpensesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ScheduleMajorCategoriesOfInvestmentIncomeNetOfExpensesTable_3369190d-c7cb-4e99-ad01-ec11a70c563b" xlink:href="rga-20240630.xsd#rga_ScheduleMajorCategoriesOfInvestmentIncomeNetOfExpensesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_rga_MajorCategoriesOfInvestmentIncomeNetOfExpensesLineItems_3746d0c2-0ad6-4d53-ae4e-2c9e2b3d6afb" xlink:to="loc_rga_ScheduleMajorCategoriesOfInvestmentIncomeNetOfExpensesTable_3369190d-c7cb-4e99-ad01-ec11a70c563b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MajorCategoriesOfInvestmentsAxis_ac9c0905-956d-4913-b78a-d379de695fe4" xlink:href="rga-20240630.xsd#rga_MajorCategoriesOfInvestmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_ScheduleMajorCategoriesOfInvestmentIncomeNetOfExpensesTable_3369190d-c7cb-4e99-ad01-ec11a70c563b" xlink:to="loc_rga_MajorCategoriesOfInvestmentsAxis_ac9c0905-956d-4913-b78a-d379de695fe4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MajorCategoriesOfInvestmentsDomain_ac9c0905-956d-4913-b78a-d379de695fe4_default" xlink:href="rga-20240630.xsd#rga_MajorCategoriesOfInvestmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_MajorCategoriesOfInvestmentsAxis_ac9c0905-956d-4913-b78a-d379de695fe4" xlink:to="loc_rga_MajorCategoriesOfInvestmentsDomain_ac9c0905-956d-4913-b78a-d379de695fe4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:href="rga-20240630.xsd#rga_MajorCategoriesOfInvestmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_MajorCategoriesOfInvestmentsAxis_ac9c0905-956d-4913-b78a-d379de695fe4" xlink:to="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableforsaleSecuritiesMember_d78f0f60-5555-4ed0-8171-5f44860ace3b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableforsaleSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:to="loc_us-gaap_AvailableforsaleSecuritiesMember_d78f0f60-5555-4ed0-8171-5f44860ace3b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_241d71f1-a2c0-4343-bd5e-58849ab4c717" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:to="loc_us-gaap_EquitySecuritiesMember_241d71f1-a2c0-4343-bd5e-58849ab4c717" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgagesMember_14ed2048-3ea3-41e2-b297-b70cb415bde9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MortgagesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:to="loc_us-gaap_MortgagesMember_14ed2048-3ea3-41e2-b297-b70cb415bde9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyLoansMember_adbbdf82-f2e4-4060-8ecf-e78b2091e6ee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PolicyLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:to="loc_us-gaap_PolicyLoansMember_adbbdf82-f2e4-4060-8ecf-e78b2091e6ee" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FundsWithheldAtInterestMember_ddb47d36-3200-4a2c-af03-1f5f770b3e99" xlink:href="rga-20240630.xsd#rga_FundsWithheldAtInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:to="loc_rga_FundsWithheldAtInterestMember_ddb47d36-3200-4a2c-af03-1f5f770b3e99" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestmentsMember_a2e76791-dcdf-4559-9a26-9d825ecb130d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortTermInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:to="loc_us-gaap_ShortTermInvestmentsMember_a2e76791-dcdf-4559-9a26-9d825ecb130d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_PartnershipInterestMember_a8a3bf24-7922-499c-936d-0f014d83aa1a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_PartnershipInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:to="loc_srt_PartnershipInterestMember_a8a3bf24-7922-499c-936d-0f014d83aa1a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAggregatedInvestmentsMember_1299c35d-0bd4-48ce-a37e-3b4cbe720c13" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherAggregatedInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentsDomain_c608c03e-2ec5-426a-a814-f9feb3c1c603" xlink:to="loc_us-gaap_OtherAggregatedInvestmentsMember_1299c35d-0bd4-48ce-a37e-3b4cbe720c13" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_InvestmentRevenue_5056f285-b885-4930-ad97-0a72b379a7a4" xlink:href="rga-20240630.xsd#rga_InvestmentRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentIncomeNetOfExpensesLineItems_3746d0c2-0ad6-4d53-ae4e-2c9e2b3d6afb" xlink:to="loc_rga_InvestmentRevenue_5056f285-b885-4930-ad97-0a72b379a7a4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInvestmentExpense_5d8c317d-fe56-452c-a33e-e11937b928ce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeInvestmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentIncomeNetOfExpensesLineItems_3746d0c2-0ad6-4d53-ae4e-2c9e2b3d6afb" xlink:to="loc_us-gaap_InvestmentIncomeInvestmentExpense_5d8c317d-fe56-452c-a33e-e11937b928ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentIncome_d3884811-230c-4107-a126-cd8c6e5da1bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NetInvestmentIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MajorCategoriesOfInvestmentIncomeNetOfExpensesLineItems_3746d0c2-0ad6-4d53-ae4e-2c9e2b3d6afb" xlink:to="loc_us-gaap_NetInvestmentIncome_d3884811-230c-4107-a126-cd8c6e5da1bc" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsBorrowedSecuritiesRepurchasedSecuritiesAndRepurchasedReversedRepurchasedSecuritiesDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsBorrowedSecuritiesRepurchasedSecuritiesAndRepurchasedReversedRepurchasedSecuritiesDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsBorrowedSecuritiesRepurchasedSecuritiesAndRepurchasedReversedRepurchasedSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionLineItems_1afe446e-6498-4e26-bb8e-1d018e0ffe50" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesFinancingTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionTable_91c5bf52-32ef-4801-9412-9c06fb0b83f5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesFinancingTransactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_1afe446e-6498-4e26-bb8e-1d018e0ffe50" xlink:to="loc_us-gaap_SecuritiesFinancingTransactionTable_91c5bf52-32ef-4801-9412-9c06fb0b83f5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionAxis_30a496e6-d899-47c2-9f13-019dc87bcd06" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesFinancingTransactionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionTable_91c5bf52-32ef-4801-9412-9c06fb0b83f5" xlink:to="loc_us-gaap_SecuritiesFinancingTransactionAxis_30a496e6-d899-47c2-9f13-019dc87bcd06" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionTypeDomain_30a496e6-d899-47c2-9f13-019dc87bcd06_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesFinancingTransactionTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionAxis_30a496e6-d899-47c2-9f13-019dc87bcd06" xlink:to="loc_us-gaap_SecuritiesFinancingTransactionTypeDomain_30a496e6-d899-47c2-9f13-019dc87bcd06_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionTypeDomain_a368a1ee-1e49-489f-b874-cde089f44616" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesFinancingTransactionTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionAxis_30a496e6-d899-47c2-9f13-019dc87bcd06" xlink:to="loc_us-gaap_SecuritiesFinancingTransactionTypeDomain_a368a1ee-1e49-489f-b874-cde089f44616" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionFairValueMember_f0ac8509-bf6d-4b18-88f8-ddd9e955369d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesFinancingTransactionFairValueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionTypeDomain_a368a1ee-1e49-489f-b874-cde089f44616" xlink:to="loc_us-gaap_SecuritiesFinancingTransactionFairValueMember_f0ac8509-bf6d-4b18-88f8-ddd9e955369d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember_c0144d10-c663-452d-b206-e7edb3b55ffa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionTypeDomain_a368a1ee-1e49-489f-b874-cde089f44616" xlink:to="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember_c0144d10-c663-452d-b206-e7edb3b55ffa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoanedFairValueOfCollateral_295f2422-c37f-4a11-8d22-3aeaaff57bf5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesLoanedFairValueOfCollateral"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_1afe446e-6498-4e26-bb8e-1d018e0ffe50" xlink:to="loc_us-gaap_SecuritiesLoanedFairValueOfCollateral_295f2422-c37f-4a11-8d22-3aeaaff57bf5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoaned_ecf47a3c-ae4c-44eb-befa-45a2374f575f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesLoaned"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_1afe446e-6498-4e26-bb8e-1d018e0ffe50" xlink:to="loc_us-gaap_SecuritiesLoaned_ecf47a3c-ae4c-44eb-befa-45a2374f575f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesBorrowed_92b7d9f5-e381-4985-b729-30db1b95f49a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesBorrowed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_1afe446e-6498-4e26-bb8e-1d018e0ffe50" xlink:to="loc_us-gaap_SecuritiesBorrowed_92b7d9f5-e381-4985-b729-30db1b95f49a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCollateralForBorrowedSecurities_4023b33f-6693-4412-a1bd-ca9132bcafda" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashCollateralForBorrowedSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_1afe446e-6498-4e26-bb8e-1d018e0ffe50" xlink:to="loc_us-gaap_CashCollateralForBorrowedSecurities_4023b33f-6693-4412-a1bd-ca9132bcafda" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsSecuritiesPledgedasCollateralRelatedtoRepurchaseReverseRepurchaseProgramDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsSecuritiesPledgedasCollateralRelatedtoRepurchaseReverseRepurchaseProgramDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsSecuritiesPledgedasCollateralRelatedtoRepurchaseReverseRepurchaseProgramDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseLineItems_d9615a9f-97d1-44a7-a091-6a363448b54c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAssetsSoldUnderAgreementsToRepurchaseTable_04a5aaff-e05d-4c50-8b09-6c2c4090b67c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfAssetsSoldUnderAgreementsToRepurchaseTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseLineItems_d9615a9f-97d1-44a7-a091-6a363448b54c" xlink:to="loc_us-gaap_ScheduleOfAssetsSoldUnderAgreementsToRepurchaseTable_04a5aaff-e05d-4c50-8b09-6c2c4090b67c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis_4d461aad-a8d6-45f2-b731-d3e4573dae3a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAssetsSoldUnderAgreementsToRepurchaseTable_04a5aaff-e05d-4c50-8b09-6c2c4090b67c" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis_4d461aad-a8d6-45f2-b731-d3e4573dae3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_4d461aad-a8d6-45f2-b731-d3e4573dae3a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis_4d461aad-a8d6-45f2-b731-d3e4573dae3a" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_4d461aad-a8d6-45f2-b731-d3e4573dae3a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_73097789-5f28-4362-96e2-29bbb312001e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis_4d461aad-a8d6-45f2-b731-d3e4573dae3a" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_73097789-5f28-4362-96e2-29bbb312001e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MaturityOvernightMember_cb31d832-7748-44a2-a5ef-5b334f35dc3c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MaturityOvernightMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_73097789-5f28-4362-96e2-29bbb312001e" xlink:to="loc_us-gaap_MaturityOvernightMember_cb31d832-7748-44a2-a5ef-5b334f35dc3c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MaturityUpTo30DaysMember_9911a366-fc2d-4b5c-b990-1630e2108b5a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MaturityUpTo30DaysMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_73097789-5f28-4362-96e2-29bbb312001e" xlink:to="loc_us-gaap_MaturityUpTo30DaysMember_9911a366-fc2d-4b5c-b990-1630e2108b5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Maturity30To90DaysMember_1a2d66d5-2844-48f6-8b3d-aee2d1e6043a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Maturity30To90DaysMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_73097789-5f28-4362-96e2-29bbb312001e" xlink:to="loc_us-gaap_Maturity30To90DaysMember_1a2d66d5-2844-48f6-8b3d-aee2d1e6043a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MaturityOver90DaysMember_8a19eb68-c767-4753-8874-623e68952225" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MaturityOver90DaysMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_73097789-5f28-4362-96e2-29bbb312001e" xlink:to="loc_us-gaap_MaturityOver90DaysMember_8a19eb68-c767-4753-8874-623e68952225" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_7ab93e84-0210-4497-bcc9-169e0b0bc023" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAssetsSoldUnderAgreementsToRepurchaseTable_04a5aaff-e05d-4c50-8b09-6c2c4090b67c" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_7ab93e84-0210-4497-bcc9-169e0b0bc023" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_7ab93e84-0210-4497-bcc9-169e0b0bc023_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_7ab93e84-0210-4497-bcc9-169e0b0bc023" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_7ab93e84-0210-4497-bcc9-169e0b0bc023_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_7ab93e84-0210-4497-bcc9-169e0b0bc023" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_1c5b0842-e567-425e-8e85-065c7dbdadb6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_1c5b0842-e567-425e-8e85-065c7dbdadb6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_4089129e-c9f0-4bb1-a805-4e23610e7f05" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_4089129e-c9f0-4bb1-a805-4e23610e7f05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_ef928294-a3fb-4ef8-9efa-5142c83f6c68" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_ef928294-a3fb-4ef8-9efa-5142c83f6c68" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CanadianProvincialGovernmentsMember_1348c9e7-b962-4d7c-bae7-70843405619b" xlink:href="rga-20240630.xsd#rga_CanadianProvincialGovernmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_rga_CanadianProvincialGovernmentsMember_1348c9e7-b962-4d7c-bae7-70843405619b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_0c019237-6f95-411c-b9f7-0e22b906488c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_0c019237-6f95-411c-b9f7-0e22b906488c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_6be34414-8efc-4dff-86c9-0640e9ee7e2c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_6be34414-8efc-4dff-86c9-0640e9ee7e2c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_b8bb99c1-8287-4e3f-9523-1515a4ba2e61" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_b8bb99c1-8287-4e3f-9523-1515a4ba2e61" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_JP_74262a92-586f-419f-bb99-70305978185c" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_JP"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_country_JP_74262a92-586f-419f-bb99-70305978185c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_71c295d8-2f3a-41d7-b52d-8ea6970f3d58" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_cb0c4290-d2f5-4239-a3d9-229907ded44a" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_71c295d8-2f3a-41d7-b52d-8ea6970f3d58" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoanedFairValueOfCollateral_bc66956b-6526-483e-9dfc-ae9c173a2513" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SecuritiesLoanedFairValueOfCollateral"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseLineItems_d9615a9f-97d1-44a7-a091-6a363448b54c" xlink:to="loc_us-gaap_SecuritiesLoanedFairValueOfCollateral_bc66956b-6526-483e-9dfc-ae9c173a2513" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetsSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement_92a276ff-0204-4737-9bc8-9efa4c317fd2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialAssetsSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseLineItems_d9615a9f-97d1-44a7-a091-6a363448b54c" xlink:to="loc_us-gaap_FinancialAssetsSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement_92a276ff-0204-4737-9bc8-9efa4c317fd2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ObligationToReturnSecuritiesReceivedAsCollateral_2a74a80a-1687-4574-8daf-07502b53582c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ObligationToReturnSecuritiesReceivedAsCollateral"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseLineItems_d9615a9f-97d1-44a7-a091-6a363448b54c" xlink:to="loc_us-gaap_ObligationToReturnSecuritiesReceivedAsCollateral_2a74a80a-1687-4574-8daf-07502b53582c" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsMortgageLoansbyPropertyTypeDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsMortgageLoansbyPropertyTypeDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsMortgageLoansbyPropertyTypeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateLineItems_29248a4a-74e4-49b4-bcb3-e6796eb1a1eb" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MortgageLoansOnRealEstateLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateScheduleTable_88a3abf3-820c-4595-99d3-898293178a5e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MortgageLoansOnRealEstateScheduleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_29248a4a-74e4-49b4-bcb3-e6796eb1a1eb" xlink:to="loc_srt_MortgageLoansOnRealEstateScheduleTable_88a3abf3-820c-4595-99d3-898293178a5e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_4992a950-a3e4-4c2c-946b-419e5d2cedd8" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_MortgageLoansOnRealEstateScheduleTable_88a3abf3-820c-4595-99d3-898293178a5e" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_4992a950-a3e4-4c2c-946b-419e5d2cedd8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_4992a950-a3e4-4c2c-946b-419e5d2cedd8_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_4992a950-a3e4-4c2c-946b-419e5d2cedd8" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_4992a950-a3e4-4c2c-946b-419e5d2cedd8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_c69b5167-e2b3-4c41-ade0-8d780c3b1394" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_4992a950-a3e4-4c2c-946b-419e5d2cedd8" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_c69b5167-e2b3-4c41-ade0-8d780c3b1394" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OfficeBuildingMember_fb4f0a0a-1c7b-41ff-ac84-9911d38e619e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_OfficeBuildingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_c69b5167-e2b3-4c41-ade0-8d780c3b1394" xlink:to="loc_srt_OfficeBuildingMember_fb4f0a0a-1c7b-41ff-ac84-9911d38e619e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RetailSiteMember_82c63c5c-939a-4d4f-85eb-1ebc3b65337e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RetailSiteMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_c69b5167-e2b3-4c41-ade0-8d780c3b1394" xlink:to="loc_srt_RetailSiteMember_82c63c5c-939a-4d4f-85eb-1ebc3b65337e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_IndustrialPropertyMember_69bbff4c-2c34-4899-ac84-3f9cc9aabd67" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_IndustrialPropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_c69b5167-e2b3-4c41-ade0-8d780c3b1394" xlink:to="loc_srt_IndustrialPropertyMember_69bbff4c-2c34-4899-ac84-3f9cc9aabd67" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ApartmentBuildingMember_da3b5855-8648-4e05-999e-fe1c8fd6b51e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ApartmentBuildingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_c69b5167-e2b3-4c41-ade0-8d780c3b1394" xlink:to="loc_srt_ApartmentBuildingMember_da3b5855-8648-4e05-999e-fe1c8fd6b51e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OtherPropertyMember_b6e08083-7a94-42c8-bb7a-d72835648946" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_OtherPropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_c69b5167-e2b3-4c41-ade0-8d780c3b1394" xlink:to="loc_srt_OtherPropertyMember_b6e08083-7a94-42c8-bb7a-d72835648946" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_2d7c8911-84fd-428f-992c-3bce7c79273b" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_c69b5167-e2b3-4c41-ade0-8d780c3b1394" xlink:to="loc_srt_HotelMember_2d7c8911-84fd-428f-992c-3bce7c79273b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableGross_a03bb10f-e1bf-4ea7-aa27-db8bf6215804" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesReceivableGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_29248a4a-74e4-49b4-bcb3-e6796eb1a1eb" xlink:to="loc_us-gaap_NotesReceivableGross_a03bb10f-e1bf-4ea7-aa27-db8bf6215804" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums_7c57b33a-90b4-431c-8e48-33042b03bd07" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_29248a4a-74e4-49b4-bcb3-e6796eb1a1eb" xlink:to="loc_us-gaap_UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums_7c57b33a-90b4-431c-8e48-33042b03bd07" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForLoanAndLeaseLossesRealEstate_e792f771-1add-4cfa-92d8-3e51272af04a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllowanceForLoanAndLeaseLossesRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_29248a4a-74e4-49b4-bcb3-e6796eb1a1eb" xlink:to="loc_us-gaap_AllowanceForLoanAndLeaseLossesRealEstate_e792f771-1add-4cfa-92d8-3e51272af04a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet_739947d4-9f72-4d2a-8c66-cdf956da11ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_29248a4a-74e4-49b4-bcb3-e6796eb1a1eb" xlink:to="loc_us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet_739947d4-9f72-4d2a-8c66-cdf956da11ba" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal_30935e13-33f2-4792-83db-b9cf2fe13874" xlink:href="rga-20240630.xsd#rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_29248a4a-74e4-49b4-bcb3-e6796eb1a1eb" xlink:to="loc_rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal_30935e13-33f2-4792-83db-b9cf2fe13874" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsMortgageLoansbyMaturityDateDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsMortgageLoansbyMaturityDateDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsMortgageLoansbyMaturityDateDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateLineItems_ed6ddd02-0905-4631-a89f-0e88143d660c" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MortgageLoansOnRealEstateLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoanMaturityTable_ce2bbf55-35f5-4aea-bd00-55f027e6bdb3" xlink:href="rga-20240630.xsd#rga_MortgageLoanMaturityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_ed6ddd02-0905-4631-a89f-0e88143d660c" xlink:to="loc_rga_MortgageLoanMaturityTable_ce2bbf55-35f5-4aea-bd00-55f027e6bdb3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoanMaturityAxis_ef6bfb15-6694-416b-a5dc-8e50467384e3" xlink:href="rga-20240630.xsd#rga_MortgageLoanMaturityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_MortgageLoanMaturityTable_ce2bbf55-35f5-4aea-bd00-55f027e6bdb3" xlink:to="loc_rga_MortgageLoanMaturityAxis_ef6bfb15-6694-416b-a5dc-8e50467384e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoanMaturityDomain_ef6bfb15-6694-416b-a5dc-8e50467384e3_default" xlink:href="rga-20240630.xsd#rga_MortgageLoanMaturityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_MortgageLoanMaturityAxis_ef6bfb15-6694-416b-a5dc-8e50467384e3" xlink:to="loc_rga_MortgageLoanMaturityDomain_ef6bfb15-6694-416b-a5dc-8e50467384e3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoanMaturityDomain_121ae0eb-d1e5-4322-a00a-09cb3037e768" xlink:href="rga-20240630.xsd#rga_MortgageLoanMaturityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_MortgageLoanMaturityAxis_ef6bfb15-6694-416b-a5dc-8e50467384e3" xlink:to="loc_rga_MortgageLoanMaturityDomain_121ae0eb-d1e5-4322-a00a-09cb3037e768" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansOnRealEstateDueOneYearThroughFiveYearsMember_b88f54d4-7c6a-4f1a-be06-8eea7de5e4c7" xlink:href="rga-20240630.xsd#rga_MortgageLoansOnRealEstateDueOneYearThroughFiveYearsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MortgageLoanMaturityDomain_121ae0eb-d1e5-4322-a00a-09cb3037e768" xlink:to="loc_rga_MortgageLoansOnRealEstateDueOneYearThroughFiveYearsMember_b88f54d4-7c6a-4f1a-be06-8eea7de5e4c7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansOnRealEstateDueAfterFiveYearsMember_477e7d50-e4a1-42b7-ab19-059d864db12e" xlink:href="rga-20240630.xsd#rga_MortgageLoansOnRealEstateDueAfterFiveYearsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MortgageLoanMaturityDomain_121ae0eb-d1e5-4322-a00a-09cb3037e768" xlink:to="loc_rga_MortgageLoansOnRealEstateDueAfterFiveYearsMember_477e7d50-e4a1-42b7-ab19-059d864db12e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansOnRealEstateDueAfterTenYearsMember_36fb42ac-e50c-4e3c-8099-cb8c53e3fbf2" xlink:href="rga-20240630.xsd#rga_MortgageLoansOnRealEstateDueAfterTenYearsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_MortgageLoanMaturityDomain_121ae0eb-d1e5-4322-a00a-09cb3037e768" xlink:to="loc_rga_MortgageLoansOnRealEstateDueAfterTenYearsMember_36fb42ac-e50c-4e3c-8099-cb8c53e3fbf2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableGross_6b9059e5-3c96-4d7f-bf59-1daf03f0b94d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesReceivableGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_ed6ddd02-0905-4631-a89f-0e88143d660c" xlink:to="loc_us-gaap_NotesReceivableGross_6b9059e5-3c96-4d7f-bf59-1daf03f0b94d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal_b616635a-ef3b-42ef-9fd2-526867571b20" xlink:href="rga-20240630.xsd#rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_ed6ddd02-0905-4631-a89f-0e88143d660c" xlink:to="loc_rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal_b616635a-ef3b-42ef-9fd2-526867571b20" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsMortgageLoansbyCreditQualityIndicatorDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsMortgageLoansbyCreditQualityIndicatorDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsMortgageLoansbyCreditQualityIndicatorDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateLineItems_549c6583-3735-4dea-bb19-e888eb4874d5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MortgageLoansOnRealEstateLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ScheduleOfCreditQualityIndicatorsTable_05e052e1-2753-434d-8b39-3ed903816086" xlink:href="rga-20240630.xsd#rga_ScheduleOfCreditQualityIndicatorsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_549c6583-3735-4dea-bb19-e888eb4874d5" xlink:to="loc_rga_ScheduleOfCreditQualityIndicatorsTable_05e052e1-2753-434d-8b39-3ed903816086" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DebtServiceCoverageRatioByRangeAxis_7066dc4e-635c-4491-be1c-1ddd5073c4a3" xlink:href="rga-20240630.xsd#rga_DebtServiceCoverageRatioByRangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_ScheduleOfCreditQualityIndicatorsTable_05e052e1-2753-434d-8b39-3ed903816086" xlink:to="loc_rga_DebtServiceCoverageRatioByRangeAxis_7066dc4e-635c-4491-be1c-1ddd5073c4a3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DebtServiceCoverageRatioByRangeDomain_7066dc4e-635c-4491-be1c-1ddd5073c4a3_default" xlink:href="rga-20240630.xsd#rga_DebtServiceCoverageRatioByRangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_DebtServiceCoverageRatioByRangeAxis_7066dc4e-635c-4491-be1c-1ddd5073c4a3" xlink:to="loc_rga_DebtServiceCoverageRatioByRangeDomain_7066dc4e-635c-4491-be1c-1ddd5073c4a3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DebtServiceCoverageRatioByRangeDomain_c725943b-8f1c-4d52-a669-d521d08f9557" xlink:href="rga-20240630.xsd#rga_DebtServiceCoverageRatioByRangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_DebtServiceCoverageRatioByRangeAxis_7066dc4e-635c-4491-be1c-1ddd5073c4a3" xlink:to="loc_rga_DebtServiceCoverageRatioByRangeDomain_c725943b-8f1c-4d52-a669-d521d08f9557" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DebtServiceCoverageRatioRangeOneMember_fc9c4481-0ce5-4b06-abc7-3ec81480c1c0" xlink:href="rga-20240630.xsd#rga_DebtServiceCoverageRatioRangeOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_DebtServiceCoverageRatioByRangeDomain_c725943b-8f1c-4d52-a669-d521d08f9557" xlink:to="loc_rga_DebtServiceCoverageRatioRangeOneMember_fc9c4481-0ce5-4b06-abc7-3ec81480c1c0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DebtServiceCoverageRatioRangeTwoMember_26b688b3-85bb-4f51-baa5-219a344ab8be" xlink:href="rga-20240630.xsd#rga_DebtServiceCoverageRatioRangeTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_DebtServiceCoverageRatioByRangeDomain_c725943b-8f1c-4d52-a669-d521d08f9557" xlink:to="loc_rga_DebtServiceCoverageRatioRangeTwoMember_26b688b3-85bb-4f51-baa5-219a344ab8be" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DebtServiceCoverageRatioRangeThreeMember_bfa7b657-ee81-4bd8-aa5b-a20145991d80" xlink:href="rga-20240630.xsd#rga_DebtServiceCoverageRatioRangeThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_DebtServiceCoverageRatioByRangeDomain_c725943b-8f1c-4d52-a669-d521d08f9557" xlink:to="loc_rga_DebtServiceCoverageRatioRangeThreeMember_bfa7b657-ee81-4bd8-aa5b-a20145991d80" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanToValueAxis_a6bdccb3-699e-4f4d-99af-ce6eb3f8df67" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoanToValueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_ScheduleOfCreditQualityIndicatorsTable_05e052e1-2753-434d-8b39-3ed903816086" xlink:to="loc_us-gaap_LoanToValueAxis_a6bdccb3-699e-4f4d-99af-ce6eb3f8df67" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanToValueDomain_a6bdccb3-699e-4f4d-99af-ce6eb3f8df67_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoanToValueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LoanToValueAxis_a6bdccb3-699e-4f4d-99af-ce6eb3f8df67" xlink:to="loc_us-gaap_LoanToValueDomain_a6bdccb3-699e-4f4d-99af-ce6eb3f8df67_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanToValueDomain_67db06f3-6816-4898-b948-cc4e871a7499" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoanToValueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LoanToValueAxis_a6bdccb3-699e-4f4d-99af-ce6eb3f8df67" xlink:to="loc_us-gaap_LoanToValueDomain_67db06f3-6816-4898-b948-cc4e871a7499" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansByCreditQualityIndicatorRangeOneMember_b53dae71-abe6-4336-a2b2-a89ba2d418f7" xlink:href="rga-20240630.xsd#rga_MortgageLoansByCreditQualityIndicatorRangeOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanToValueDomain_67db06f3-6816-4898-b948-cc4e871a7499" xlink:to="loc_rga_MortgageLoansByCreditQualityIndicatorRangeOneMember_b53dae71-abe6-4336-a2b2-a89ba2d418f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansByCreditQualityIndicatorRangeTwoMember_08802608-4b4d-4270-8291-64f4eb313acd" xlink:href="rga-20240630.xsd#rga_MortgageLoansByCreditQualityIndicatorRangeTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanToValueDomain_67db06f3-6816-4898-b948-cc4e871a7499" xlink:to="loc_rga_MortgageLoansByCreditQualityIndicatorRangeTwoMember_08802608-4b4d-4270-8291-64f4eb313acd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansByCreditQualityIndicatorRangeThreeMember_f9ce4674-61df-4bee-bafa-fa34feeb9e9a" xlink:href="rga-20240630.xsd#rga_MortgageLoansByCreditQualityIndicatorRangeThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanToValueDomain_67db06f3-6816-4898-b948-cc4e871a7499" xlink:to="loc_rga_MortgageLoansByCreditQualityIndicatorRangeThreeMember_f9ce4674-61df-4bee-bafa-fa34feeb9e9a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansByCreditQualityIndicatorRangeFourMember_83ec06d6-bf3a-4ac6-b345-78c4b144e235" xlink:href="rga-20240630.xsd#rga_MortgageLoansByCreditQualityIndicatorRangeFourMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanToValueDomain_67db06f3-6816-4898-b948-cc4e871a7499" xlink:to="loc_rga_MortgageLoansByCreditQualityIndicatorRangeFourMember_83ec06d6-bf3a-4ac6-b345-78c4b144e235" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableGross_8339bdbe-837d-4c36-a0b3-9a13ee4dfe8a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesReceivableGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_549c6583-3735-4dea-bb19-e888eb4874d5" xlink:to="loc_us-gaap_NotesReceivableGross_8339bdbe-837d-4c36-a0b3-9a13ee4dfe8a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConstructionLoan_9f5c3c30-c7bc-4e88-b804-ae968ace80ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ConstructionLoan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_549c6583-3735-4dea-bb19-e888eb4874d5" xlink:to="loc_us-gaap_ConstructionLoan_9f5c3c30-c7bc-4e88-b804-ae968ace80ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal_4b791f8d-25ac-44ba-a1d3-8526d34e6a97" xlink:href="rga-20240630.xsd#rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateLineItems_549c6583-3735-4dea-bb19-e888eb4874d5" xlink:to="loc_rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal_4b791f8d-25ac-44ba-a1d3-8526d34e6a97" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsInternalCreditRatingDisclosureDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsInternalCreditRatingDisclosureDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsInternalCreditRatingDisclosureDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_7ca9b611-613a-442e-a270-66db08f78b3a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_9abb4468-3287-4366-afd3-ef455f266bd4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_7ca9b611-613a-442e-a270-66db08f78b3a" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_9abb4468-3287-4366-afd3-ef455f266bd4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearofOriginationAxis_c2d719f3-d14f-4342-87e7-5569a5c8fe5d" xlink:href="rga-20240630.xsd#rga_YearofOriginationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_9abb4468-3287-4366-afd3-ef455f266bd4" xlink:to="loc_rga_YearofOriginationAxis_c2d719f3-d14f-4342-87e7-5569a5c8fe5d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearofOriginationDomain_c2d719f3-d14f-4342-87e7-5569a5c8fe5d_default" xlink:href="rga-20240630.xsd#rga_YearofOriginationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_YearofOriginationAxis_c2d719f3-d14f-4342-87e7-5569a5c8fe5d" xlink:to="loc_rga_YearofOriginationDomain_c2d719f3-d14f-4342-87e7-5569a5c8fe5d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:href="rga-20240630.xsd#rga_YearofOriginationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_YearofOriginationAxis_c2d719f3-d14f-4342-87e7-5569a5c8fe5d" xlink:to="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearOfOrigination2024Member_d1f27a4e-1d53-456a-9f1b-3e0e7387b498" xlink:href="rga-20240630.xsd#rga_YearOfOrigination2024Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:to="loc_rga_YearOfOrigination2024Member_d1f27a4e-1d53-456a-9f1b-3e0e7387b498" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearOfOrigination2023Member_f4b9699c-ff90-437c-a7ef-4661803dc7c4" xlink:href="rga-20240630.xsd#rga_YearOfOrigination2023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:to="loc_rga_YearOfOrigination2023Member_f4b9699c-ff90-437c-a7ef-4661803dc7c4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearOfOrigination2022Member_8c24ab9f-2678-4fc4-bba5-fcd0c225ade9" xlink:href="rga-20240630.xsd#rga_YearOfOrigination2022Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:to="loc_rga_YearOfOrigination2022Member_8c24ab9f-2678-4fc4-bba5-fcd0c225ade9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearOfOrigination2021Member_8e05251b-b6c7-4fac-8f74-ff011ece6f98" xlink:href="rga-20240630.xsd#rga_YearOfOrigination2021Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:to="loc_rga_YearOfOrigination2021Member_8e05251b-b6c7-4fac-8f74-ff011ece6f98" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearOfOrigination2020Member_6d7091c2-6da8-4712-a7da-c2b8a973c563" xlink:href="rga-20240630.xsd#rga_YearOfOrigination2020Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:to="loc_rga_YearOfOrigination2020Member_6d7091c2-6da8-4712-a7da-c2b8a973c563" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearOfOrigination2019Member_cfb2ba32-1137-4f36-b216-52c7b072c2f6" xlink:href="rga-20240630.xsd#rga_YearOfOrigination2019Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:to="loc_rga_YearOfOrigination2019Member_cfb2ba32-1137-4f36-b216-52c7b072c2f6" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_YearOfOriginationPriorPeriodsMember_08c05252-be83-41d9-af86-df347b5a44a2" xlink:href="rga-20240630.xsd#rga_YearOfOriginationPriorPeriodsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_YearofOriginationDomain_4e841c2f-8b1b-4044-9b25-942b3df2d289" xlink:to="loc_rga_YearOfOriginationPriorPeriodsMember_08c05252-be83-41d9-af86-df347b5a44a2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis_973b9469-1002-4aeb-8b7b-bcd2cad57abd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_9abb4468-3287-4366-afd3-ef455f266bd4" xlink:to="loc_us-gaap_InternalCreditAssessmentAxis_973b9469-1002-4aeb-8b7b-bcd2cad57abd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_973b9469-1002-4aeb-8b7b-bcd2cad57abd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_973b9469-1002-4aeb-8b7b-bcd2cad57abd" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_973b9469-1002-4aeb-8b7b-bcd2cad57abd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_68d5ab73-011e-4d87-9d80-7ff4fd99fae0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_973b9469-1002-4aeb-8b7b-bcd2cad57abd" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_68d5ab73-011e-4d87-9d80-7ff4fd99fae0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_HighInvestmentGradeMember_d7bfd8c0-8190-4acd-aa66-3d236a075983" xlink:href="rga-20240630.xsd#rga_HighInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_68d5ab73-011e-4d87-9d80-7ff4fd99fae0" xlink:to="loc_rga_HighInvestmentGradeMember_d7bfd8c0-8190-4acd-aa66-3d236a075983" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalInvestmentGradeMember_a1569c5a-6fd8-43f8-8950-441bf13af6ce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InternalInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_68d5ab73-011e-4d87-9d80-7ff4fd99fae0" xlink:to="loc_us-gaap_InternalInvestmentGradeMember_a1569c5a-6fd8-43f8-8950-441bf13af6ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_AverageInvestmentGradeMember_05ea0a62-db53-45cf-8e00-62ff73e490be" xlink:href="rga-20240630.xsd#rga_AverageInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_68d5ab73-011e-4d87-9d80-7ff4fd99fae0" xlink:to="loc_rga_AverageInvestmentGradeMember_05ea0a62-db53-45cf-8e00-62ff73e490be" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalNoninvestmentGradeMember_01401733-325a-4d53-94a4-1ded826a9a31" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InternalNoninvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_68d5ab73-011e-4d87-9d80-7ff4fd99fae0" xlink:to="loc_us-gaap_InternalNoninvestmentGradeMember_01401733-325a-4d53-94a4-1ded826a9a31" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_WatchListMember_a1a4dc46-4592-4aa6-a569-ca568688dc35" xlink:href="rga-20240630.xsd#rga_WatchListMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_68d5ab73-011e-4d87-9d80-7ff4fd99fae0" xlink:to="loc_rga_WatchListMember_a1a4dc46-4592-4aa6-a569-ca568688dc35" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableGross_2c77c50e-04c8-4abd-8236-40904abf1666" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesReceivableGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_7ca9b611-613a-442e-a270-66db08f78b3a" xlink:to="loc_us-gaap_NotesReceivableGross_2c77c50e-04c8-4abd-8236-40904abf1666" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsFinancingReceivablesPastDueDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsFinancingReceivablesPastDueDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsFinancingReceivablesPastDueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_05cead88-dabd-4f1f-8113-feea6a43b337" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_d1c9e992-6714-405a-bdb3-0165a94c1de9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfFinancingReceivablesPastDueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_05cead88-dabd-4f1f-8113-feea6a43b337" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_d1c9e992-6714-405a-bdb3-0165a94c1de9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_8170f4c2-2caf-4d3e-a3b0-f575f8af0ad3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_d1c9e992-6714-405a-bdb3-0165a94c1de9" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_8170f4c2-2caf-4d3e-a3b0-f575f8af0ad3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_8170f4c2-2caf-4d3e-a3b0-f575f8af0ad3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_8170f4c2-2caf-4d3e-a3b0-f575f8af0ad3" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_8170f4c2-2caf-4d3e-a3b0-f575f8af0ad3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_d1b5ee6e-1ca8-4e6c-82e9-2f558ef2d549" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_8170f4c2-2caf-4d3e-a3b0-f575f8af0ad3" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_d1b5ee6e-1ca8-4e6c-82e9-2f558ef2d549" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetNotPastDueMember_6b929a2b-5da2-4c25-a703-23ab46cbb257" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialAssetNotPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_d1b5ee6e-1ca8-4e6c-82e9-2f558ef2d549" xlink:to="loc_us-gaap_FinancialAssetNotPastDueMember_6b929a2b-5da2-4c25-a703-23ab46cbb257" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_3e17affb-14f2-4e20-bb6f-eac678829fd7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivables30To59DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_d1b5ee6e-1ca8-4e6c-82e9-2f558ef2d549" xlink:to="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_3e17affb-14f2-4e20-bb6f-eac678829fd7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_35510055-e9cd-4b31-87ef-f5212b054202" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_d1b5ee6e-1ca8-4e6c-82e9-2f558ef2d549" xlink:to="loc_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_35510055-e9cd-4b31-87ef-f5212b054202" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableGross_a2985caa-232b-4d9a-9871-3399599da349" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesReceivableGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_05cead88-dabd-4f1f-8113-feea6a43b337" xlink:to="loc_us-gaap_NotesReceivableGross_a2985caa-232b-4d9a-9871-3399599da349" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsOtherInvestedAssetsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsOtherInvestedAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsOtherInvestedAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_bc98522e-d978-42c9-8eaf-7bc804f99f2b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_2e557d0a-ce6e-4ad0-a431-137fb8c1ab08" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_bc98522e-d978-42c9-8eaf-7bc804f99f2b" xlink:to="loc_us-gaap_StatementTable_2e557d0a-ce6e-4ad0-a431-137fb8c1ab08" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_5973dd2a-99bb-45f9-be5c-efc560054933" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_2e557d0a-ce6e-4ad0-a431-137fb8c1ab08" xlink:to="loc_us-gaap_InvestmentTypeAxis_5973dd2a-99bb-45f9-be5c-efc560054933" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_5973dd2a-99bb-45f9-be5c-efc560054933_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_5973dd2a-99bb-45f9-be5c-efc560054933" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_5973dd2a-99bb-45f9-be5c-efc560054933_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_f97aecb7-5fdb-4066-94ed-8d5461db1768" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_5973dd2a-99bb-45f9-be5c-efc560054933" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_f97aecb7-5fdb-4066-94ed-8d5461db1768" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LimitedPartnerMember_a21c82f1-6b5b-4406-80c0-34ca6d861907" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LimitedPartnerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_f97aecb7-5fdb-4066-94ed-8d5461db1768" xlink:to="loc_us-gaap_LimitedPartnerMember_a21c82f1-6b5b-4406-80c0-34ca6d861907" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_EquityReleaseMortgagesMember_114d5147-028c-49e5-9d6d-0c2236009a04" xlink:href="rga-20240630.xsd#rga_EquityReleaseMortgagesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_f97aecb7-5fdb-4066-94ed-8d5461db1768" xlink:to="loc_rga_EquityReleaseMortgagesMember_114d5147-028c-49e5-9d6d-0c2236009a04" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeMember_f9bc2e7b-3f47-4fcb-90f1-82623eb5cd06" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_f97aecb7-5fdb-4066-94ed-8d5461db1768" xlink:to="loc_us-gaap_DerivativeMember_f9bc2e7b-3f47-4fcb-90f1-82623eb5cd06" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCreditDerivativesMember_6adffe26-f386-475b-ad6b-1f3308b2cf36" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCreditDerivativesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_f97aecb7-5fdb-4066-94ed-8d5461db1768" xlink:to="loc_us-gaap_OtherCreditDerivativesMember_6adffe26-f386-475b-ad6b-1f3308b2cf36" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankCertificatesAndObligationsFHLBMember_65befc08-ae5e-4425-9671-9374fb37913a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FederalHomeLoanBankCertificatesAndObligationsFHLBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_f97aecb7-5fdb-4066-94ed-8d5461db1768" xlink:to="loc_us-gaap_FederalHomeLoanBankCertificatesAndObligationsFHLBMember_65befc08-ae5e-4425-9671-9374fb37913a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInvestments_d4d0f128-e1d4-439c-9d55-2be339892438" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_bc98522e-d978-42c9-8eaf-7bc804f99f2b" xlink:to="loc_us-gaap_OtherInvestments_d4d0f128-e1d4-439c-9d55-2be339892438" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsLimitedPartnershipsandRealEstateJointVenturesDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsLimitedPartnershipsandRealEstateJointVenturesDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsLimitedPartnershipsandRealEstateJointVenturesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateLineItems_7e2927f8-441f-47ab-ad8c-4f0cc63f66d8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RealEstateLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateTable_4f4a25cf-2294-4087-b629-77615c7e21c4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RealEstateTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RealEstateLineItems_7e2927f8-441f-47ab-ad8c-4f0cc63f66d8" xlink:to="loc_us-gaap_RealEstateTable_4f4a25cf-2294-4087-b629-77615c7e21c4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_LimitedPartnershipClassificationAxisAxis_e82faa6a-d627-4521-99c7-44cf98230b47" xlink:href="rga-20240630.xsd#rga_LimitedPartnershipClassificationAxisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RealEstateTable_4f4a25cf-2294-4087-b629-77615c7e21c4" xlink:to="loc_rga_LimitedPartnershipClassificationAxisAxis_e82faa6a-d627-4521-99c7-44cf98230b47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_LimitedPartnershipClassificationAxisDomain_e82faa6a-d627-4521-99c7-44cf98230b47_default" xlink:href="rga-20240630.xsd#rga_LimitedPartnershipClassificationAxisDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_LimitedPartnershipClassificationAxisAxis_e82faa6a-d627-4521-99c7-44cf98230b47" xlink:to="loc_rga_LimitedPartnershipClassificationAxisDomain_e82faa6a-d627-4521-99c7-44cf98230b47_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_LimitedPartnershipClassificationAxisDomain_cdf034a3-28af-4889-a572-aaaee4b641be" xlink:href="rga-20240630.xsd#rga_LimitedPartnershipClassificationAxisDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_LimitedPartnershipClassificationAxisAxis_e82faa6a-d627-4521-99c7-44cf98230b47" xlink:to="loc_rga_LimitedPartnershipClassificationAxisDomain_cdf034a3-28af-4889-a572-aaaee4b641be" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentsMember_5b5c5474-9322-47e4-8cf1-4f1d9cd57b70" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMethodInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_LimitedPartnershipClassificationAxisDomain_cdf034a3-28af-4889-a572-aaaee4b641be" xlink:to="loc_us-gaap_EquityMethodInvestmentsMember_5b5c5474-9322-47e4-8cf1-4f1d9cd57b70" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_LimitedPartnershipFairValueMemberMember_a0660d99-2ffb-4bbe-93d5-7952be3a4c8c" xlink:href="rga-20240630.xsd#rga_LimitedPartnershipFairValueMemberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_LimitedPartnershipClassificationAxisDomain_cdf034a3-28af-4889-a572-aaaee4b641be" xlink:to="loc_rga_LimitedPartnershipFairValueMemberMember_a0660d99-2ffb-4bbe-93d5-7952be3a4c8c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateJointVentureMember_3a9e1345-dfd7-4d73-8344-e2059b32ae98" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateJointVentureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_LimitedPartnershipClassificationAxisDomain_cdf034a3-28af-4889-a572-aaaee4b641be" xlink:to="loc_us-gaap_CorporateJointVentureMember_3a9e1345-dfd7-4d73-8344-e2059b32ae98" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_LimitedPartnershipCostMethodMember_9c37e740-4a64-48a6-8a77-1325867b209f" xlink:href="rga-20240630.xsd#rga_LimitedPartnershipCostMethodMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_LimitedPartnershipClassificationAxisDomain_cdf034a3-28af-4889-a572-aaaee4b641be" xlink:to="loc_rga_LimitedPartnershipCostMethodMember_9c37e740-4a64-48a6-8a77-1325867b209f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateInvestmentsJointVentures_6826479e-c7df-46ff-94da-3fa773b08561" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RealEstateInvestmentsJointVentures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstateLineItems_7e2927f8-441f-47ab-ad8c-4f0cc63f66d8" xlink:to="loc_us-gaap_RealEstateInvestmentsJointVentures_6826479e-c7df-46ff-94da-3fa773b08561" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/InvestmentsNarrativeDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#InvestmentsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/InvestmentsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:href="rga-20240630.xsd#rga_InvestmentNarrativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_InvestmentNarrativeTable_6099fd8b-b35f-42aa-8e31-7ea79ba314c7" xlink:href="rga-20240630.xsd#rga_InvestmentNarrativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_rga_InvestmentNarrativeTable_6099fd8b-b35f-42aa-8e31-7ea79ba314c7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicDistributionAxis_31db4371-5b33-415d-baf7-395721db367e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GeographicDistributionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_InvestmentNarrativeTable_6099fd8b-b35f-42aa-8e31-7ea79ba314c7" xlink:to="loc_us-gaap_GeographicDistributionAxis_31db4371-5b33-415d-baf7-395721db367e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicDistributionDomain_31db4371-5b33-415d-baf7-395721db367e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GeographicDistributionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GeographicDistributionAxis_31db4371-5b33-415d-baf7-395721db367e" xlink:to="loc_us-gaap_GeographicDistributionDomain_31db4371-5b33-415d-baf7-395721db367e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicDistributionDomain_d90ded73-2d77-4a18-ad8e-994ae4f9723b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GeographicDistributionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GeographicDistributionAxis_31db4371-5b33-415d-baf7-395721db367e" xlink:to="loc_us-gaap_GeographicDistributionDomain_d90ded73-2d77-4a18-ad8e-994ae4f9723b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_CA_40e6f38b-d5e6-418a-b453-3ce91437ad61" xlink:href="https://xbrl.sec.gov/stpr/2024/stpr-2024.xsd#stpr_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GeographicDistributionDomain_d90ded73-2d77-4a18-ad8e-994ae4f9723b" xlink:to="loc_stpr_CA_40e6f38b-d5e6-418a-b453-3ce91437ad61" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_TX_18eb130a-3dd6-42a9-a80c-02b598265342" xlink:href="https://xbrl.sec.gov/stpr/2024/stpr-2024.xsd#stpr_TX"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GeographicDistributionDomain_d90ded73-2d77-4a18-ad8e-994ae4f9723b" xlink:to="loc_stpr_TX_18eb130a-3dd6-42a9-a80c-02b598265342" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_e409bbc2-910b-4329-8580-ec43db8d11a2" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GeographicDistributionDomain_d90ded73-2d77-4a18-ad8e-994ae4f9723b" xlink:to="loc_country_CA_e409bbc2-910b-4329-8580-ec43db8d11a2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_dd981e9f-c788-489e-b2d0-0319d9b32d87" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GeographicDistributionDomain_d90ded73-2d77-4a18-ad8e-994ae4f9723b" xlink:to="loc_country_GB_dd981e9f-c788-489e-b2d0-0319d9b32d87" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_stpr_WA_04072bd3-cc67-4594-9630-19e13d712caf" xlink:href="https://xbrl.sec.gov/stpr/2024/stpr-2024.xsd#stpr_WA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GeographicDistributionDomain_d90ded73-2d77-4a18-ad8e-994ae4f9723b" xlink:to="loc_stpr_WA_04072bd3-cc67-4594-9630-19e13d712caf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_da22a06b-bfa9-45cb-a6f9-6a9521b30496" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_InvestmentNarrativeTable_6099fd8b-b35f-42aa-8e31-7ea79ba314c7" xlink:to="loc_us-gaap_InvestmentTypeAxis_da22a06b-bfa9-45cb-a6f9-6a9521b30496" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_da22a06b-bfa9-45cb-a6f9-6a9521b30496_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_da22a06b-bfa9-45cb-a6f9-6a9521b30496" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_da22a06b-bfa9-45cb-a6f9-6a9521b30496_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_1062569f-4389-43c9-993c-25e08807b39e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_da22a06b-bfa9-45cb-a6f9-6a9521b30496" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_1062569f-4389-43c9-993c-25e08807b39e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_70d64a81-9e6d-4976-9422-d565564ec16e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_InvestmentNarrativeTable_6099fd8b-b35f-42aa-8e31-7ea79ba314c7" xlink:to="loc_us-gaap_FinancialInstrumentAxis_70d64a81-9e6d-4976-9422-d565564ec16e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_70d64a81-9e6d-4976-9422-d565564ec16e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_70d64a81-9e6d-4976-9422-d565564ec16e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_70d64a81-9e6d-4976-9422-d565564ec16e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_210ec3f7-a1e6-4ac1-8ea5-4a4daa1ae26e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_70d64a81-9e6d-4976-9422-d565564ec16e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_210ec3f7-a1e6-4ac1-8ea5-4a4daa1ae26e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_c5668d55-b1d4-4c85-8740-d4129230aa93" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_210ec3f7-a1e6-4ac1-8ea5-4a4daa1ae26e" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_c5668d55-b1d4-4c85-8740-d4129230aa93" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingAxis_d3156c75-7d5e-446e-9e05-1a20c6628996" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingByGroupingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_InvestmentNarrativeTable_6099fd8b-b35f-42aa-8e31-7ea79ba314c7" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingAxis_d3156c75-7d5e-446e-9e05-1a20c6628996" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingDomain_d3156c75-7d5e-446e-9e05-1a20c6628996_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingByGroupingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingAxis_d3156c75-7d5e-446e-9e05-1a20c6628996" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingDomain_d3156c75-7d5e-446e-9e05-1a20c6628996_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingDomain_dfa4c5a9-6de5-41a5-b9ad-0c5130702a84" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingByGroupingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingAxis_d3156c75-7d5e-446e-9e05-1a20c6628996" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingDomain_dfa4c5a9-6de5-41a5-b9ad-0c5130702a84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingNonInvestmentGradeMember_d6a8c86d-c931-473f-8886-18e4faf9d7d5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ExternalCreditRatingNonInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingDomain_dfa4c5a9-6de5-41a5-b9ad-0c5130702a84" xlink:to="loc_us-gaap_ExternalCreditRatingNonInvestmentGradeMember_d6a8c86d-c931-473f-8886-18e4faf9d7d5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_96e6fb5e-c9c9-41a4-bbea-27d9803a074f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_InvestmentNarrativeTable_6099fd8b-b35f-42aa-8e31-7ea79ba314c7" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_96e6fb5e-c9c9-41a4-bbea-27d9803a074f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_96e6fb5e-c9c9-41a4-bbea-27d9803a074f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_96e6fb5e-c9c9-41a4-bbea-27d9803a074f" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_96e6fb5e-c9c9-41a4-bbea-27d9803a074f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_1358f7e1-4913-461d-88dc-c1e3e20bac48" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_96e6fb5e-c9c9-41a4-bbea-27d9803a074f" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_1358f7e1-4913-461d-88dc-c1e3e20bac48" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_SecuritiesAsPercentageOfConsolidatedStockholderEquity_ec16e23d-2206-4045-a0d0-6d43803ad7ad" xlink:href="rga-20240630.xsd#rga_SecuritiesAsPercentageOfConsolidatedStockholderEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_rga_SecuritiesAsPercentageOfConsolidatedStockholderEquity_ec16e23d-2206-4045-a0d0-6d43803ad7ad" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal_fd04af66-6f40-49a9-8c40-8a42d7ca8acb" xlink:href="rga-20240630.xsd#rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal_fd04af66-6f40-49a9-8c40-8a42d7ca8acb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsAsset_101c935d-5e66-4c14-98c0-79cc317af30c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FundsHeldUnderReinsuranceAgreementsAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsAsset_101c935d-5e66-4c14-98c0-79cc317af30c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FundsHeldUnderReinsuranceAgreementsAssetSpecificClient_d877013e-d5b4-4d75-972e-1f67909bc645" xlink:href="rga-20240630.xsd#rga_FundsHeldUnderReinsuranceAgreementsAssetSpecificClient"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_rga_FundsHeldUnderReinsuranceAgreementsAssetSpecificClient_d877013e-d5b4-4d75-972e-1f67909bc645" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions_4a6a2745-5329-48dc-a990-f7c453fda8ff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions_4a6a2745-5329-48dc-a990-f7c453fda8ff" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableGross_61573e17-9060-4770-a2aa-78bb7312d697" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NotesReceivableGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_us-gaap_NotesReceivableGross_61573e17-9060-4770-a2aa-78bb7312d697" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransferToOtherRealEstate_cbe4ea54-b8ec-4c41-8edc-895f464f60d0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransferToOtherRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_us-gaap_TransferToOtherRealEstate_cbe4ea54-b8ec-4c41-8edc-895f464f60d0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageLoansInProcessOfForeclosureAmount_934170cc-e4df-45ce-954e-f28cfc2f1228" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MortgageLoansInProcessOfForeclosureAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_us-gaap_MortgageLoansInProcessOfForeclosureAmount_934170cc-e4df-45ce-954e-f28cfc2f1228" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNoncurrentNonaccrual_0537404d-cf1d-4351-bf20-8e871043cd26" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccountsReceivableNoncurrentNonaccrual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_us-gaap_AccountsReceivableNoncurrentNonaccrual_0537404d-cf1d-4351-bf20-8e871043cd26" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_RealEstateReclassifiedToHeldForUse_256f9ff8-ae00-4862-8ca7-3ab19f7e45d3" xlink:href="rga-20240630.xsd#rga_RealEstateReclassifiedToHeldForUse"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_InvestmentNarrativeLineItems_424eaeb2-7b29-49ca-9696-dc29b66e0203" xlink:to="loc_rga_RealEstateReclassifiedToHeldForUse_256f9ff8-ae00-4862-8ca7-3ab19f7e45d3" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsGrossNotionalAmountandFairValueofDerivativesContractsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsGrossNotionalAmountandFairValueofDerivativesContractsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsGrossNotionalAmountandFairValueofDerivativesContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_7b649b2b-6840-41d0-8940-2d4dd367a8dc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_0e9e4c9f-9db3-4cd3-8535-42e07c3da739" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_7b649b2b-6840-41d0-8940-2d4dd367a8dc" xlink:to="loc_us-gaap_DerivativeTable_0e9e4c9f-9db3-4cd3-8535-42e07c3da739" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_457b0a9d-0a69-4384-aeb1-ebbf55402a60" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_0e9e4c9f-9db3-4cd3-8535-42e07c3da739" xlink:to="loc_us-gaap_HedgingDesignationAxis_457b0a9d-0a69-4384-aeb1-ebbf55402a60" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_457b0a9d-0a69-4384-aeb1-ebbf55402a60_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_457b0a9d-0a69-4384-aeb1-ebbf55402a60" xlink:to="loc_us-gaap_HedgingDesignationDomain_457b0a9d-0a69-4384-aeb1-ebbf55402a60_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_c0c95eb9-e817-4905-8e85-29e3175c4088" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_457b0a9d-0a69-4384-aeb1-ebbf55402a60" xlink:to="loc_us-gaap_HedgingDesignationDomain_c0c95eb9-e817-4905-8e85-29e3175c4088" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_9b779174-2867-4ce8-b149-0db7719ae6d2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_c0c95eb9-e817-4905-8e85-29e3175c4088" xlink:to="loc_us-gaap_NondesignatedMember_9b779174-2867-4ce8-b149-0db7719ae6d2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_31e08deb-88b4-4988-a7fd-081044cd5a8f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_c0c95eb9-e817-4905-8e85-29e3175c4088" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_31e08deb-88b4-4988-a7fd-081044cd5a8f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_b938fc34-63f5-4e78-8759-77af23ba01e6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_0e9e4c9f-9db3-4cd3-8535-42e07c3da739" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_b938fc34-63f5-4e78-8759-77af23ba01e6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_b938fc34-63f5-4e78-8759-77af23ba01e6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_b938fc34-63f5-4e78-8759-77af23ba01e6" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_b938fc34-63f5-4e78-8759-77af23ba01e6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_b938fc34-63f5-4e78-8759-77af23ba01e6" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_de15de21-c32c-478f-b07e-ee40b8a89910" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_InterestRateSwapMember_de15de21-c32c-478f-b07e-ee40b8a89910" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_b06c4d98-c586-4665-8a64-5dedaae7b7e8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_b06c4d98-c586-4665-8a64-5dedaae7b7e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FutureMember_e3083026-4056-41d3-a923-c92a4a244bed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FutureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_FutureMember_e3083026-4056-41d3-a923-c92a4a244bed" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ConsumerPriceIndexSwapMember_aa3f6ae6-2ce3-432a-a8b3-a23d95971421" xlink:href="rga-20240630.xsd#rga_ConsumerPriceIndexSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_rga_ConsumerPriceIndexSwapMember_aa3f6ae6-2ce3-432a-a8b3-a23d95971421" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMember_88bcc0f5-775a-45a4-b5bb-ebab5c4ba690" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_EquityMember_88bcc0f5-775a-45a4-b5bb-ebab5c4ba690" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_SyntheticGuaranteedInvestmentContractsMember_25fdd277-b113-49a1-af2a-a387de90f8cb" xlink:href="rga-20240630.xsd#rga_SyntheticGuaranteedInvestmentContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_rga_SyntheticGuaranteedInvestmentContractsMember_25fdd277-b113-49a1-af2a-a387de90f8cb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_EmbeddedDerivativesInModifiedCoinsuranceOrFundsWithheldArrangementsMember_5e5f323e-15ac-45f8-a4cc-eb4f862106db" xlink:href="rga-20240630.xsd#rga_EmbeddedDerivativesInModifiedCoinsuranceOrFundsWithheldArrangementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_rga_EmbeddedDerivativesInModifiedCoinsuranceOrFundsWithheldArrangementsMember_5e5f323e-15ac-45f8-a4cc-eb4f862106db" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_EmbeddedDerivativesInIndexedAnnuityMember_8332979b-365a-4035-a9e4-304de745a33f" xlink:href="rga-20240630.xsd#rga_EmbeddedDerivativesInIndexedAnnuityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_rga_EmbeddedDerivativesInIndexedAnnuityMember_8332979b-365a-4035-a9e4-304de745a33f" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrencySwapMember_95f82c59-94fe-4900-bf8d-f601d5783941" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CurrencySwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_CurrencySwapMember_95f82c59-94fe-4900-bf8d-f601d5783941" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForwardContractsMember_5716e265-93d1-45fe-b66e-b02ce244e956" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForwardContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_ForwardContractsMember_5716e265-93d1-45fe-b66e-b02ce244e956" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwaptionMember_b51884c0-202f-4527-9fc1-c21756c4fa8c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateSwaptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_InterestRateSwaptionMember_b51884c0-202f-4527-9fc1-c21756c4fa8c" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TotalReturnSwapMember_26fe7ebe-e0be-42ba-83fa-97fe32c2fac7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TotalReturnSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_TotalReturnSwapMember_26fe7ebe-e0be-42ba-83fa-97fe32c2fac7" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_InterestRateFutureMember_8d8c58f8-b62a-49dc-8efe-18613ff196af" xlink:href="rga-20240630.xsd#rga_InterestRateFutureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_rga_InterestRateFutureMember_8d8c58f8-b62a-49dc-8efe-18613ff196af" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeOptionMember_f1a57c52-c770-4b2a-9feb-ecda7402bc73" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_ForeignExchangeOptionMember_f1a57c52-c770-4b2a-9feb-ecda7402bc73" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockOptionMember_7cf4857e-3e3b-464e-860e-20a58d4184db" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_StockOptionMember_7cf4857e-3e3b-464e-860e-20a58d4184db" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDefaultSwapMember_a3fdbf15-d219-49ec-9e80-e1a2d69a31c0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_c1e47773-3757-4c3b-86a9-a9e08ca21047" xlink:to="loc_us-gaap_CreditDefaultSwapMember_a3fdbf15-d219-49ec-9e80-e1a2d69a31c0" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_c37ee646-5f0c-4c8b-aa2c-81142c61d20e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_7b649b2b-6840-41d0-8940-2d4dd367a8dc" xlink:to="loc_us-gaap_DerivativeNotionalAmount_c37ee646-5f0c-4c8b-aa2c-81142c61d20e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_10ae5351-078e-4aa2-bdad-6cef0d61fd39" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeFairValueOfDerivativeAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_7b649b2b-6840-41d0-8940-2d4dd367a8dc" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_10ae5351-078e-4aa2-bdad-6cef0d61fd39" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_7b425408-a3b8-4706-9ae3-6c3378f6b153" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeFairValueOfDerivativeLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_7b649b2b-6840-41d0-8940-2d4dd367a8dc" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_7b425408-a3b8-4706-9ae3-6c3378f6b153" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement_3a733c87-865b-4c8d-a799-5575df45a2c3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_7b649b2b-6840-41d0-8940-2d4dd367a8dc" xlink:to="loc_us-gaap_DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement_3a733c87-865b-4c8d-a799-5575df45a2c3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement_b9342d2e-e1b7-42ab-80af-dd27b766b178" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_7b649b2b-6840-41d0-8940-2d4dd367a8dc" xlink:to="loc_us-gaap_DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement_b9342d2e-e1b7-42ab-80af-dd27b766b178" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsFairValueHedgeAttributabletoForeignCurrencyDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsFairValueHedgeAttributabletoForeignCurrencyDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsFairValueHedgeAttributabletoForeignCurrencyDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6821bf40-8729-4db4-a21e-c1886c2bccd5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_f67f1b5e-06d5-4197-a750-82f961fafa43" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6821bf40-8729-4db4-a21e-c1886c2bccd5" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_f67f1b5e-06d5-4197-a750-82f961fafa43" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_1cc68512-4768-43bf-9adb-cf28e1818b53" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_f67f1b5e-06d5-4197-a750-82f961fafa43" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_1cc68512-4768-43bf-9adb-cf28e1818b53" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_1cc68512-4768-43bf-9adb-cf28e1818b53_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_1cc68512-4768-43bf-9adb-cf28e1818b53" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_1cc68512-4768-43bf-9adb-cf28e1818b53_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_ecdfc6f3-7385-490c-9b3b-733f80186ee5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_1cc68512-4768-43bf-9adb-cf28e1818b53" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_ecdfc6f3-7385-490c-9b3b-733f80186ee5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_b4dd1a25-fe31-401e-9907-81141e1f1e0e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_ecdfc6f3-7385-490c-9b3b-733f80186ee5" xlink:to="loc_us-gaap_ForeignExchangeContractMember_b4dd1a25-fe31-401e-9907-81141e1f1e0e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_b0a53c26-4a00-45ac-9580-75ca2819301d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_ecdfc6f3-7385-490c-9b3b-733f80186ee5" xlink:to="loc_us-gaap_InterestRateContractMember_b0a53c26-4a00-45ac-9580-75ca2819301d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FutureMember_cb15f075-4fb7-4655-8a3a-9942eae8332f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FutureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_ecdfc6f3-7385-490c-9b3b-733f80186ee5" xlink:to="loc_us-gaap_FutureMember_cb15f075-4fb7-4655-8a3a-9942eae8332f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_cdccc4f7-d0fb-4283-84e2-ee38eda37342" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_f67f1b5e-06d5-4197-a750-82f961fafa43" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_cdccc4f7-d0fb-4283-84e2-ee38eda37342" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_cdccc4f7-d0fb-4283-84e2-ee38eda37342_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_cdccc4f7-d0fb-4283-84e2-ee38eda37342" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_cdccc4f7-d0fb-4283-84e2-ee38eda37342_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_c6547110-2462-4ad4-bf84-f8926db7cf23" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_cdccc4f7-d0fb-4283-84e2-ee38eda37342" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_c6547110-2462-4ad4-bf84-f8926db7cf23" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseMember_03fcd534-8d06-4059-a3cc-a531e8b95bd3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_c6547110-2462-4ad4-bf84-f8926db7cf23" xlink:to="loc_us-gaap_InterestExpenseMember_03fcd534-8d06-4059-a3cc-a531e8b95bd3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InsuranceClaimsMember_43173e5f-e008-4eec-b4ec-9b10a052d227" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InsuranceClaimsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_c6547110-2462-4ad4-bf84-f8926db7cf23" xlink:to="loc_us-gaap_InsuranceClaimsMember_43173e5f-e008-4eec-b4ec-9b10a052d227" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeExpenseMember_d7b2bd4b-d0d8-4b19-a219-bc0eae66375c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_c6547110-2462-4ad4-bf84-f8926db7cf23" xlink:to="loc_us-gaap_InvestmentIncomeExpenseMember_d7b2bd4b-d0d8-4b19-a219-bc0eae66375c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1_2501ff7c-6658-40dd-8564-8fb30687704b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6821bf40-8729-4db4-a21e-c1886c2bccd5" xlink:to="loc_us-gaap_ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1_2501ff7c-6658-40dd-8564-8fb30687704b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnFairValueHedgeIneffectivenessNet_4c24c959-ef8a-4d0f-b847-79054bf8e87b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnFairValueHedgeIneffectivenessNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6821bf40-8729-4db4-a21e-c1886c2bccd5" xlink:to="loc_us-gaap_GainLossOnFairValueHedgeIneffectivenessNet_4c24c959-ef8a-4d0f-b847-79054bf8e87b" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsCurrentPeriodCashFlowHedgesinAOCIlossbeforeTaxesDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsCurrentPeriodCashFlowHedgesinAOCIlossbeforeTaxesDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsCurrentPeriodCashFlowHedgesinAOCIlossbeforeTaxesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_9e61eb01-30ea-4cf3-bdcf-0450936be03c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_88106753-f6e8-4ee8-948c-ee2d6c35ff9e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_9e61eb01-30ea-4cf3-bdcf-0450936be03c" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_88106753-f6e8-4ee8-948c-ee2d6c35ff9e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_a56f0785-076e-4490-8de0-eef3de67d0df" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_88106753-f6e8-4ee8-948c-ee2d6c35ff9e" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_a56f0785-076e-4490-8de0-eef3de67d0df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_a56f0785-076e-4490-8de0-eef3de67d0df_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_a56f0785-076e-4490-8de0-eef3de67d0df" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_a56f0785-076e-4490-8de0-eef3de67d0df_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_a97851f0-32fd-436d-91f8-de2619096dfd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_a56f0785-076e-4490-8de0-eef3de67d0df" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_a97851f0-32fd-436d-91f8-de2619096dfd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeMember_fc652131-3013-4e0a-a377-9f05bf3dd7b5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_a97851f0-32fd-436d-91f8-de2619096dfd" xlink:to="loc_us-gaap_InvestmentIncomeMember_fc652131-3013-4e0a-a377-9f05bf3dd7b5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseMember_52cddd1a-0d36-4953-972b-4975716db71b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_a97851f0-32fd-436d-91f8-de2619096dfd" xlink:to="loc_us-gaap_InterestExpenseMember_52cddd1a-0d36-4953-972b-4975716db71b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_253ac54d-df6b-4685-887f-365b68c2f82a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_88106753-f6e8-4ee8-948c-ee2d6c35ff9e" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_253ac54d-df6b-4685-887f-365b68c2f82a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_253ac54d-df6b-4685-887f-365b68c2f82a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_253ac54d-df6b-4685-887f-365b68c2f82a" xlink:to="loc_us-gaap_HedgingRelationshipDomain_253ac54d-df6b-4685-887f-365b68c2f82a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_af6b02ed-174a-45d9-8481-988a7caad287" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_253ac54d-df6b-4685-887f-365b68c2f82a" xlink:to="loc_us-gaap_HedgingRelationshipDomain_af6b02ed-174a-45d9-8481-988a7caad287" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_4854a1a3-79e4-4c47-8dad-9cbf8673a11e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_af6b02ed-174a-45d9-8481-988a7caad287" xlink:to="loc_us-gaap_CashFlowHedgingMember_4854a1a3-79e4-4c47-8dad-9cbf8673a11e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_06e0ef99-e8d5-4a39-836b-f70ec0be4330" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_9e61eb01-30ea-4cf3-bdcf-0450936be03c" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_06e0ef99-e8d5-4a39-836b-f70ec0be4330" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax_661ea859-a701-4502-a5ed-374dd24cf647" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_9e61eb01-30ea-4cf3-bdcf-0450936be03c" xlink:to="loc_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax_661ea859-a701-4502-a5ed-374dd24cf647" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DerivativeGainLossNetDeferredInOCI_94d42974-1837-4063-b562-60fb872badde" xlink:href="rga-20240630.xsd#rga_DerivativeGainLossNetDeferredInOCI"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_9e61eb01-30ea-4cf3-bdcf-0450936be03c" xlink:to="loc_rga_DerivativeGainLossNetDeferredInOCI_94d42974-1837-4063-b562-60fb872badde" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsCashFlowHedgesDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsCashFlowHedgesDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsCashFlowHedgesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_31617838-7685-430a-a5ef-ecd1031ee0f5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_929ff596-5d9e-44c9-a5c6-a6139e9b3b0c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_31617838-7685-430a-a5ef-ecd1031ee0f5" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_929ff596-5d9e-44c9-a5c6-a6139e9b3b0c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_17e0a5e9-42da-4695-a892-cae6b7427d4e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_929ff596-5d9e-44c9-a5c6-a6139e9b3b0c" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_17e0a5e9-42da-4695-a892-cae6b7427d4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_17e0a5e9-42da-4695-a892-cae6b7427d4e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_17e0a5e9-42da-4695-a892-cae6b7427d4e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_17e0a5e9-42da-4695-a892-cae6b7427d4e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_a533c3d8-c582-43ac-8479-7bbe376ca3d9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_17e0a5e9-42da-4695-a892-cae6b7427d4e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_a533c3d8-c582-43ac-8479-7bbe376ca3d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_3af60060-08bb-47ed-89d9-afc77c75290d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_a533c3d8-c582-43ac-8479-7bbe376ca3d9" xlink:to="loc_us-gaap_InterestRateSwapMember_3af60060-08bb-47ed-89d9-afc77c75290d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrencySwapMember_f8abaf68-8338-45b9-92e6-3b93c7294770" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CurrencySwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_a533c3d8-c582-43ac-8479-7bbe376ca3d9" xlink:to="loc_us-gaap_CurrencySwapMember_f8abaf68-8338-45b9-92e6-3b93c7294770" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_0127cd14-a374-4d29-9f7e-f5143be2a2d2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_929ff596-5d9e-44c9-a5c6-a6139e9b3b0c" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_0127cd14-a374-4d29-9f7e-f5143be2a2d2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_0127cd14-a374-4d29-9f7e-f5143be2a2d2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_0127cd14-a374-4d29-9f7e-f5143be2a2d2" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_0127cd14-a374-4d29-9f7e-f5143be2a2d2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_f56447d9-034a-4d36-9953-2ae07f0746b9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_0127cd14-a374-4d29-9f7e-f5143be2a2d2" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_f56447d9-034a-4d36-9953-2ae07f0746b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeMember_d5f5baa4-aaa8-4d74-96c3-91d898fbf39b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_f56447d9-034a-4d36-9953-2ae07f0746b9" xlink:to="loc_us-gaap_InvestmentIncomeMember_d5f5baa4-aaa8-4d74-96c3-91d898fbf39b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseMember_36a1ea3f-3fcd-4af9-b28b-b0dce8cb5c0b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_f56447d9-034a-4d36-9953-2ae07f0746b9" xlink:to="loc_us-gaap_InterestExpenseMember_36a1ea3f-3fcd-4af9-b28b-b0dce8cb5c0b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_150add66-b6a8-4f63-81eb-35c99395cf8a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_929ff596-5d9e-44c9-a5c6-a6139e9b3b0c" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_150add66-b6a8-4f63-81eb-35c99395cf8a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_150add66-b6a8-4f63-81eb-35c99395cf8a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_150add66-b6a8-4f63-81eb-35c99395cf8a" xlink:to="loc_us-gaap_HedgingRelationshipDomain_150add66-b6a8-4f63-81eb-35c99395cf8a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_97a3c300-8cbd-421c-81a3-eb0ce3837f9f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_150add66-b6a8-4f63-81eb-35c99395cf8a" xlink:to="loc_us-gaap_HedgingRelationshipDomain_97a3c300-8cbd-421c-81a3-eb0ce3837f9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_b36171d3-ebd8-460a-8573-3a950b4cdf89" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_97a3c300-8cbd-421c-81a3-eb0ce3837f9f" xlink:to="loc_us-gaap_CashFlowHedgingMember_b36171d3-ebd8-460a-8573-3a950b4cdf89" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DerivativeGainLossDeferredInOCI_49f83788-f961-4890-8dc6-b0e7e88292ab" xlink:href="rga-20240630.xsd#rga_DerivativeGainLossDeferredInOCI"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_31617838-7685-430a-a5ef-ecd1031ee0f5" xlink:to="loc_rga_DerivativeGainLossDeferredInOCI_49f83788-f961-4890-8dc6-b0e7e88292ab" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_b601947f-6079-4a26-8897-683efdefa6cc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_31617838-7685-430a-a5ef-ecd1031ee0f5" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_b601947f-6079-4a26-8897-683efdefa6cc" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsHedgesofNetInvestmentsinForeignOperationsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsHedgesofNetInvestmentsinForeignOperationsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsHedgesofNetInvestmentsinForeignOperationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativesFairValueLineItems_c73098b3-b0ea-45be-96b8-745dcef029ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativesFairValueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_9d6a7c82-9a08-4a84-9372-151279383516" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_c73098b3-b0ea-45be-96b8-745dcef029ed" xlink:to="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_9d6a7c82-9a08-4a84-9372-151279383516" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_e68791f2-2687-4a1e-8d68-f7deeb7e8932" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_9d6a7c82-9a08-4a84-9372-151279383516" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_e68791f2-2687-4a1e-8d68-f7deeb7e8932" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_e68791f2-2687-4a1e-8d68-f7deeb7e8932_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_e68791f2-2687-4a1e-8d68-f7deeb7e8932" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_e68791f2-2687-4a1e-8d68-f7deeb7e8932_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_57636a55-d6fa-4171-ab88-e39de28415e6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_e68791f2-2687-4a1e-8d68-f7deeb7e8932" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_57636a55-d6fa-4171-ab88-e39de28415e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrencySwapMember_349d331e-f268-41a1-83d9-279142e294eb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CurrencySwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_57636a55-d6fa-4171-ab88-e39de28415e6" xlink:to="loc_us-gaap_CurrencySwapMember_349d331e-f268-41a1-83d9-279142e294eb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_220c40b2-a339-409b-82cb-e1ce28dff8b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_57636a55-d6fa-4171-ab88-e39de28415e6" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_220c40b2-a339-409b-82cb-e1ce28dff8b0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_GainsLossesDeferredInAccumulatedOtherComprehensiveIncomeLossOnDerivativesEffectivePortion_f4902306-d3d4-4c0b-b9bd-3dd1415a6e6a" xlink:href="rga-20240630.xsd#rga_GainsLossesDeferredInAccumulatedOtherComprehensiveIncomeLossOnDerivativesEffectivePortion"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_c73098b3-b0ea-45be-96b8-745dcef029ed" xlink:to="loc_rga_GainsLossesDeferredInAccumulatedOtherComprehensiveIncomeLossOnDerivativesEffectivePortion_f4902306-d3d4-4c0b-b9bd-3dd1415a6e6a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsNonHedgingDerivativesandEmbeddedDerivativesEffectonIncomeStatementDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsNonHedgingDerivativesandEmbeddedDerivativesEffectonIncomeStatementDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsNonHedgingDerivativesandEmbeddedDerivativesEffectonIncomeStatementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_rga_IncomeAffectOfNonHedgingDerivativesLineItems_8305e822-3a78-45b2-8a17-0a643e6972e5" xlink:href="rga-20240630.xsd#rga_IncomeAffectOfNonHedgingDerivativesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_NonHedgingDerivativesTable_7385e65b-e2be-4964-b98b-08b64c1250cd" xlink:href="rga-20240630.xsd#rga_NonHedgingDerivativesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_rga_IncomeAffectOfNonHedgingDerivativesLineItems_8305e822-3a78-45b2-8a17-0a643e6972e5" xlink:to="loc_rga_NonHedgingDerivativesTable_7385e65b-e2be-4964-b98b-08b64c1250cd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_d9279309-f460-4101-a6b2-b9698f91da66" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_NonHedgingDerivativesTable_7385e65b-e2be-4964-b98b-08b64c1250cd" xlink:to="loc_us-gaap_HedgingDesignationAxis_d9279309-f460-4101-a6b2-b9698f91da66" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_d9279309-f460-4101-a6b2-b9698f91da66_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_d9279309-f460-4101-a6b2-b9698f91da66" xlink:to="loc_us-gaap_HedgingDesignationDomain_d9279309-f460-4101-a6b2-b9698f91da66_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_51e90206-f55a-46e1-85a8-4b7ce7aec4d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_d9279309-f460-4101-a6b2-b9698f91da66" xlink:to="loc_us-gaap_HedgingDesignationDomain_51e90206-f55a-46e1-85a8-4b7ce7aec4d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_129b0f76-5b12-4320-8198-3f70550f0f1f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_51e90206-f55a-46e1-85a8-4b7ce7aec4d6" xlink:to="loc_us-gaap_NondesignatedMember_129b0f76-5b12-4320-8198-3f70550f0f1f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_DerivativesNonHedgingInstrumentsAxis_0b59f3b9-f355-43ac-a98c-66b13c5e7539" xlink:href="rga-20240630.xsd#rga_DerivativesNonHedgingInstrumentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_rga_NonHedgingDerivativesTable_7385e65b-e2be-4964-b98b-08b64c1250cd" xlink:to="loc_rga_DerivativesNonHedgingInstrumentsAxis_0b59f3b9-f355-43ac-a98c-66b13c5e7539" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_NonHedgingInstrumentsDomain_0b59f3b9-f355-43ac-a98c-66b13c5e7539_default" xlink:href="rga-20240630.xsd#rga_NonHedgingInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_DerivativesNonHedgingInstrumentsAxis_0b59f3b9-f355-43ac-a98c-66b13c5e7539" xlink:to="loc_rga_NonHedgingInstrumentsDomain_0b59f3b9-f355-43ac-a98c-66b13c5e7539_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:href="rga-20240630.xsd#rga_NonHedgingInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_DerivativesNonHedgingInstrumentsAxis_0b59f3b9-f355-43ac-a98c-66b13c5e7539" xlink:to="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_9df224da-3ec7-4c53-886e-ca6084fd0f24" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_InterestRateSwapMember_9df224da-3ec7-4c53-886e-ca6084fd0f24" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FutureMember_c88c03d4-09be-4c62-ba94-9bf03bcad38b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FutureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_FutureMember_c88c03d4-09be-4c62-ba94-9bf03bcad38b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrencySwapMember_d1a3a6c6-f5fc-435e-858e-21d7b1751aeb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CurrencySwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_CurrencySwapMember_d1a3a6c6-f5fc-435e-858e-21d7b1751aeb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_26c12025-7a28-4bd9-a25d-99402d1488cf" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_26c12025-7a28-4bd9-a25d-99402d1488cf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_ConsumerPriceIndexSwapMember_5b9dc77e-8f76-46c0-8dc3-634b6e1c8bb6" xlink:href="rga-20240630.xsd#rga_ConsumerPriceIndexSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_rga_ConsumerPriceIndexSwapMember_5b9dc77e-8f76-46c0-8dc3-634b6e1c8bb6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMember_15aa5438-698f-49e3-9a59-31eaeea80350" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_EquityMember_15aa5438-698f-49e3-9a59-31eaeea80350" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_EmbeddedDerivativesInModifiedCoinsuranceOrFundsWithheldArrangementsMember_d580f42f-69f1-420d-9744-d91869fd62b0" xlink:href="rga-20240630.xsd#rga_EmbeddedDerivativesInModifiedCoinsuranceOrFundsWithheldArrangementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_rga_EmbeddedDerivativesInModifiedCoinsuranceOrFundsWithheldArrangementsMember_d580f42f-69f1-420d-9744-d91869fd62b0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_EmbeddedDerivativesInIndexedAnnuityMember_77ed736b-ba17-4ed5-ac16-eb0a28296232" xlink:href="rga-20240630.xsd#rga_EmbeddedDerivativesInIndexedAnnuityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_rga_EmbeddedDerivativesInIndexedAnnuityMember_77ed736b-ba17-4ed5-ac16-eb0a28296232" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_InterestRateFutureMember_2a1eff06-75da-4118-9a43-682a97970a43" xlink:href="rga-20240630.xsd#rga_InterestRateFutureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_rga_InterestRateFutureMember_2a1eff06-75da-4118-9a43-682a97970a43" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TotalReturnSwapMember_f8833790-3822-4324-8420-c5a5f647292d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TotalReturnSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_TotalReturnSwapMember_f8833790-3822-4324-8420-c5a5f647292d" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwaptionMember_a5d89abe-7f29-4866-90b8-9ef9d0ddcb76" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateSwaptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_InterestRateSwaptionMember_a5d89abe-7f29-4866-90b8-9ef9d0ddcb76" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDefaultSwapMember_0d9c0019-5f2d-408c-bab1-2d754292127a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_CreditDefaultSwapMember_0d9c0019-5f2d-408c-bab1-2d754292127a" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeOptionMember_2511f644-807e-47c8-bdf2-58af4747159b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignExchangeOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_NonHedgingInstrumentsDomain_b954f2ea-3cab-4218-b84f-dcd1ffa60251" xlink:to="loc_us-gaap_ForeignExchangeOptionMember_2511f644-807e-47c8-bdf2-58af4747159b" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnInvestments_ed4c51c7-60e8-4fff-8744-bf61f343f536" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_IncomeAffectOfNonHedgingDerivativesLineItems_8305e822-3a78-45b2-8a17-0a643e6972e5" xlink:to="loc_us-gaap_GainLossOnInvestments_ed4c51c7-60e8-4fff-8744-bf61f343f536" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_GainLossOnInvestmentsRelatedToChangeInFairValueOfDerivativesExcludingEmbeddedDerivatives_437d2265-85dc-4d0e-9cc4-b77f1a35409d" xlink:href="rga-20240630.xsd#rga_GainLossOnInvestmentsRelatedToChangeInFairValueOfDerivativesExcludingEmbeddedDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_IncomeAffectOfNonHedgingDerivativesLineItems_8305e822-3a78-45b2-8a17-0a643e6972e5" xlink:to="loc_rga_GainLossOnInvestmentsRelatedToChangeInFairValueOfDerivativesExcludingEmbeddedDerivatives_437d2265-85dc-4d0e-9cc4-b77f1a35409d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestCreditedToPolicyholdersAccountBalances_7d2aade5-e70c-47d7-a8bd-a740a4b126ba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestCreditedToPolicyholdersAccountBalances"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_IncomeAffectOfNonHedgingDerivativesLineItems_8305e822-3a78-45b2-8a17-0a643e6972e5" xlink:to="loc_us-gaap_InterestCreditedToPolicyholdersAccountBalances_7d2aade5-e70c-47d7-a8bd-a740a4b126ba" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsExposurefromCreditDerivativesbyRatingoftheUnderlyingCreditsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsExposurefromCreditDerivativesbyRatingoftheUnderlyingCreditsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsExposurefromCreditDerivativesbyRatingoftheUnderlyingCreditsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesLineItems_938eae23-4b4d-4855-b24a-79bf7414d4c7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditDerivativesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_b9729c2a-f019-4872-8783-39f2f39a262d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CreditDerivativesLineItems_938eae23-4b4d-4855-b24a-79bf7414d4c7" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_b9729c2a-f019-4872-8783-39f2f39a262d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingStandardPoorsAxis_fc4e9831-60bc-4bf0-a8a2-c852ff791e2a" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_CreditRatingStandardPoorsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_b9729c2a-f019-4872-8783-39f2f39a262d" xlink:to="loc_srt_CreditRatingStandardPoorsAxis_fc4e9831-60bc-4bf0-a8a2-c852ff791e2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ExternalCreditRatingStandardPoorsMember_fc4e9831-60bc-4bf0-a8a2-c852ff791e2a_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ExternalCreditRatingStandardPoorsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CreditRatingStandardPoorsAxis_fc4e9831-60bc-4bf0-a8a2-c852ff791e2a" xlink:to="loc_srt_ExternalCreditRatingStandardPoorsMember_fc4e9831-60bc-4bf0-a8a2-c852ff791e2a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ExternalCreditRatingStandardPoorsMember_6b0c2cea-6eb3-4c5c-8225-a42b8ceb8f60" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ExternalCreditRatingStandardPoorsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CreditRatingStandardPoorsAxis_fc4e9831-60bc-4bf0-a8a2-c852ff791e2a" xlink:to="loc_srt_ExternalCreditRatingStandardPoorsMember_6b0c2cea-6eb3-4c5c-8225-a42b8ceb8f60" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_StandardPoorsAaaToAminusRatingsMember_4e738592-a44b-4ae1-baa5-9552fdc4fd46" xlink:href="rga-20240630.xsd#rga_StandardPoorsAaaToAminusRatingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ExternalCreditRatingStandardPoorsMember_6b0c2cea-6eb3-4c5c-8225-a42b8ceb8f60" xlink:to="loc_rga_StandardPoorsAaaToAminusRatingsMember_4e738592-a44b-4ae1-baa5-9552fdc4fd46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StandardPoorsBBBRatingMember_abeed2f1-67e4-4d18-9b68-81abe261e968" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StandardPoorsBBBRatingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ExternalCreditRatingStandardPoorsMember_6b0c2cea-6eb3-4c5c-8225-a42b8ceb8f60" xlink:to="loc_srt_StandardPoorsBBBRatingMember_abeed2f1-67e4-4d18-9b68-81abe261e968" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StandardPoorsBBRatingMember_f5b32c63-29ee-492a-821c-5c2ec9eeae42" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StandardPoorsBBRatingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ExternalCreditRatingStandardPoorsMember_6b0c2cea-6eb3-4c5c-8225-a42b8ceb8f60" xlink:to="loc_srt_StandardPoorsBBRatingMember_f5b32c63-29ee-492a-821c-5c2ec9eeae42" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StandardPoorsBRatingMember_deaee3ec-bd7c-4ec6-9137-9eac02a06094" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StandardPoorsBRatingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ExternalCreditRatingStandardPoorsMember_6b0c2cea-6eb3-4c5c-8225-a42b8ceb8f60" xlink:to="loc_srt_StandardPoorsBRatingMember_deaee3ec-bd7c-4ec6-9137-9eac02a06094" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CreditDefaultTypesAxis_73cf333a-a75d-4479-9596-7ecc3dacb52f" xlink:href="rga-20240630.xsd#rga_CreditDefaultTypesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_b9729c2a-f019-4872-8783-39f2f39a262d" xlink:to="loc_rga_CreditDefaultTypesAxis_73cf333a-a75d-4479-9596-7ecc3dacb52f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CreditDefaultTypesDomain_73cf333a-a75d-4479-9596-7ecc3dacb52f_default" xlink:href="rga-20240630.xsd#rga_CreditDefaultTypesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_CreditDefaultTypesAxis_73cf333a-a75d-4479-9596-7ecc3dacb52f" xlink:to="loc_rga_CreditDefaultTypesDomain_73cf333a-a75d-4479-9596-7ecc3dacb52f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CreditDefaultTypesDomain_fb7ad115-e6c4-404e-95e8-d6b52a6d3a17" xlink:href="rga-20240630.xsd#rga_CreditDefaultTypesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_CreditDefaultTypesAxis_73cf333a-a75d-4479-9596-7ecc3dacb52f" xlink:to="loc_rga_CreditDefaultTypesDomain_fb7ad115-e6c4-404e-95e8-d6b52a6d3a17" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_SingleNameCreditDefaultSwapsMember_23306760-7542-42e1-b7af-798d0f5914c8" xlink:href="rga-20240630.xsd#rga_SingleNameCreditDefaultSwapsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_CreditDefaultTypesDomain_fb7ad115-e6c4-404e-95e8-d6b52a6d3a17" xlink:to="loc_rga_SingleNameCreditDefaultSwapsMember_23306760-7542-42e1-b7af-798d0f5914c8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CreditDefaultSwapsReferencingIndicesMember_baf3db13-be4c-43e6-aa3d-a797a777fad3" xlink:href="rga-20240630.xsd#rga_CreditDefaultSwapsReferencingIndicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_CreditDefaultTypesDomain_fb7ad115-e6c4-404e-95e8-d6b52a6d3a17" xlink:to="loc_rga_CreditDefaultSwapsReferencingIndicesMember_baf3db13-be4c-43e6-aa3d-a797a777fad3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CreditDefaultSubtotalMember_b596d011-fc6b-48cc-b3c7-cebf6ac7cde9" xlink:href="rga-20240630.xsd#rga_CreditDefaultSubtotalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_CreditDefaultTypesDomain_fb7ad115-e6c4-404e-95e8-d6b52a6d3a17" xlink:to="loc_rga_CreditDefaultSubtotalMember_b596d011-fc6b-48cc-b3c7-cebf6ac7cde9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskDerivativesAtFairValueNet_d9658045-d1c9-425b-a436-d31d1fa2d9f4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditRiskDerivativesAtFairValueNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesLineItems_938eae23-4b4d-4855-b24a-79bf7414d4c7" xlink:to="loc_us-gaap_CreditRiskDerivativesAtFairValueNet_d9658045-d1c9-425b-a436-d31d1fa2d9f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativeMaximumExposureUndiscounted_1f6b328a-bb02-4c0d-80c8-6aff72e79096" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CreditDerivativeMaximumExposureUndiscounted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesLineItems_938eae23-4b4d-4855-b24a-79bf7414d4c7" xlink:to="loc_us-gaap_CreditDerivativeMaximumExposureUndiscounted_1f6b328a-bb02-4c0d-80c8-6aff72e79096" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAverageRemainingMaturity1_559939ed-afbe-4e5c-b563-6fbe61f48e98" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeAverageRemainingMaturity1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesLineItems_938eae23-4b4d-4855-b24a-79bf7414d4c7" xlink:to="loc_us-gaap_DerivativeAverageRemainingMaturity1_559939ed-afbe-4e5c-b563-6fbe61f48e98" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsNarrativeDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_c2214bb7-88c0-44e3-8ac0-893d50a361d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_5701ac3e-b07a-4ea8-b240-0772c0a04a0b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_c2214bb7-88c0-44e3-8ac0-893d50a361d1" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_5701ac3e-b07a-4ea8-b240-0772c0a04a0b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_c7bf5080-0d56-4301-8f1b-7d611ad859f4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_5701ac3e-b07a-4ea8-b240-0772c0a04a0b" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_c7bf5080-0d56-4301-8f1b-7d611ad859f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_c7bf5080-0d56-4301-8f1b-7d611ad859f4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_c7bf5080-0d56-4301-8f1b-7d611ad859f4" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_c7bf5080-0d56-4301-8f1b-7d611ad859f4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_dea74448-d1c4-48fe-8ff7-b833ddd8543d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_c7bf5080-0d56-4301-8f1b-7d611ad859f4" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_dea74448-d1c4-48fe-8ff7-b833ddd8543d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeMember_0ed491fd-b2b2-4e58-a04f-4d3d52405e38" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_dea74448-d1c4-48fe-8ff7-b833ddd8543d" xlink:to="loc_us-gaap_InvestmentIncomeMember_0ed491fd-b2b2-4e58-a04f-4d3d52405e38" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseMember_ab717a1d-4e11-4f96-bf5f-76dfacd64377" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_dea74448-d1c4-48fe-8ff7-b833ddd8543d" xlink:to="loc_us-gaap_InterestExpenseMember_ab717a1d-4e11-4f96-bf5f-76dfacd64377" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CumulativeForeignCurrencyTranslationGainLossRecordedInAccumulatedOtherComprehensiveIncomeLossForTerminatedNetInvestmentInForeignOperationsHedges_dc3b1f70-4843-45f5-abb3-96df26baa525" xlink:href="rga-20240630.xsd#rga_CumulativeForeignCurrencyTranslationGainLossRecordedInAccumulatedOtherComprehensiveIncomeLossForTerminatedNetInvestmentInForeignOperationsHedges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_c2214bb7-88c0-44e3-8ac0-893d50a361d1" xlink:to="loc_rga_CumulativeForeignCurrencyTranslationGainLossRecordedInAccumulatedOtherComprehensiveIncomeLossForTerminatedNetInvestmentInForeignOperationsHedges_dc3b1f70-4843-45f5-abb3-96df26baa525" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet_cd3b8d64-f435-4fc2-b774-f13bf3256b6b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_c2214bb7-88c0-44e3-8ac0-893d50a361d1" xlink:to="loc_us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet_cd3b8d64-f435-4fc2-b774-f13bf3256b6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CounterpartyCreditDerivativeExposure_e96f420f-e495-4312-b399-d52b3f36d544" xlink:href="rga-20240630.xsd#rga_CounterpartyCreditDerivativeExposure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_c2214bb7-88c0-44e3-8ac0-893d50a361d1" xlink:to="loc_rga_CounterpartyCreditDerivativeExposure_e96f420f-e495-4312-b399-d52b3f36d544" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/DerivativeInstrumentsFairValueHedgeCumulativeDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#DerivativeInstrumentsFairValueHedgeCumulativeDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/DerivativeInstrumentsFairValueHedgeCumulativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6c6634ef-bcd4-4402-82c7-b1f515b1b097" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_03b9b0f5-a64c-489a-a47d-79565b48382d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6c6634ef-bcd4-4402-82c7-b1f515b1b097" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_03b9b0f5-a64c-489a-a47d-79565b48382d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_4481f0df-f3b3-48b6-8a46-90df6d57771d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_03b9b0f5-a64c-489a-a47d-79565b48382d" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_4481f0df-f3b3-48b6-8a46-90df6d57771d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_4481f0df-f3b3-48b6-8a46-90df6d57771d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_4481f0df-f3b3-48b6-8a46-90df6d57771d" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_4481f0df-f3b3-48b6-8a46-90df6d57771d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_59d80964-72a3-45e0-8d18-a9ae4887c3e9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_4481f0df-f3b3-48b6-8a46-90df6d57771d" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_59d80964-72a3-45e0-8d18-a9ae4887c3e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_02d5d759-49bc-411a-9945-e62d6279249f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_59d80964-72a3-45e0-8d18-a9ae4887c3e9" xlink:to="loc_us-gaap_InterestRateContractMember_02d5d759-49bc-411a-9945-e62d6279249f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherContractMember_14ff72c2-6844-4bb5-be28-49218249c6c5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_59d80964-72a3-45e0-8d18-a9ae4887c3e9" xlink:to="loc_us-gaap_OtherContractMember_14ff72c2-6844-4bb5-be28-49218249c6c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_4c58ed02-ad68-4efa-b913-671975b742ee" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_03b9b0f5-a64c-489a-a47d-79565b48382d" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_4c58ed02-ad68-4efa-b913-671975b742ee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_4c58ed02-ad68-4efa-b913-671975b742ee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_4c58ed02-ad68-4efa-b913-671975b742ee" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_4c58ed02-ad68-4efa-b913-671975b742ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_5f858d22-0d35-4d57-8857-9b96eb83d6e9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_4c58ed02-ad68-4efa-b913-671975b742ee" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_5f858d22-0d35-4d57-8857-9b96eb83d6e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLocationAxis_041c06c2-7f73-4c36-a407-b61198e476b2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_03b9b0f5-a64c-489a-a47d-79565b48382d" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLocationAxis_041c06c2-7f73-4c36-a407-b61198e476b2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLocationDomain_041c06c2-7f73-4c36-a407-b61198e476b2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLocationAxis_041c06c2-7f73-4c36-a407-b61198e476b2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLocationDomain_041c06c2-7f73-4c36-a407-b61198e476b2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLocationDomain_bbf8ccc7-e5f9-4428-bb8a-aaabf3f34ed5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLocationAxis_041c06c2-7f73-4c36-a407-b61198e476b2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLocationDomain_bbf8ccc7-e5f9-4428-bb8a-aaabf3f34ed5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_f53a489a-182a-432a-82fc-b3890eb1d01e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_03b9b0f5-a64c-489a-a47d-79565b48382d" xlink:to="loc_us-gaap_HedgingDesignationAxis_f53a489a-182a-432a-82fc-b3890eb1d01e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_f53a489a-182a-432a-82fc-b3890eb1d01e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_f53a489a-182a-432a-82fc-b3890eb1d01e" xlink:to="loc_us-gaap_HedgingDesignationDomain_f53a489a-182a-432a-82fc-b3890eb1d01e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_370ef96c-6311-41ab-85db-dcd490f5f9f1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_f53a489a-182a-432a-82fc-b3890eb1d01e" xlink:to="loc_us-gaap_HedgingDesignationDomain_370ef96c-6311-41ab-85db-dcd490f5f9f1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_4e5fb0b4-1a61-4f9d-9894-77d47e8f195b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_03b9b0f5-a64c-489a-a47d-79565b48382d" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_4e5fb0b4-1a61-4f9d-9894-77d47e8f195b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_4e5fb0b4-1a61-4f9d-9894-77d47e8f195b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_4e5fb0b4-1a61-4f9d-9894-77d47e8f195b" xlink:to="loc_us-gaap_HedgingRelationshipDomain_4e5fb0b4-1a61-4f9d-9894-77d47e8f195b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_577633a1-142b-4724-a4b6-a3d82527eb65" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_4e5fb0b4-1a61-4f9d-9894-77d47e8f195b" xlink:to="loc_us-gaap_HedgingRelationshipDomain_577633a1-142b-4724-a4b6-a3d82527eb65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedge_65bb53b2-a85a-46f9-9133-4bfcca844666" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgedAssetFairValueHedge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6c6634ef-bcd4-4402-82c7-b1f515b1b097" xlink:to="loc_us-gaap_HedgedAssetFairValueHedge_65bb53b2-a85a-46f9-9133-4bfcca844666" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityFairValueHedge_72958492-3ec0-4500-aaba-55d2f9e031ff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgedLiabilityFairValueHedge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6c6634ef-bcd4-4402-82c7-b1f515b1b097" xlink:to="loc_us-gaap_HedgedLiabilityFairValueHedge_72958492-3ec0-4500-aaba-55d2f9e031ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease_de24effc-d17f-42e6-a9c5-4dbd24318853" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6c6634ef-bcd4-4402-82c7-b1f515b1b097" xlink:to="loc_us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease_de24effc-d17f-42e6-a9c5-4dbd24318853" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease_98275e54-706e-49d2-a42c-56eaa88ed1ab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_6c6634ef-bcd4-4402-82c7-b1f515b1b097" xlink:to="loc_us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease_98275e54-706e-49d2-a42c-56eaa88ed1ab" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesBalancesofAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesBalancesofAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesBalancesofAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_900e92dc-c417-49e2-9ba9-e84dd43350e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_89beeb45-ca2d-4156-9259-b5ddf755a8ed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_900e92dc-c417-49e2-9ba9-e84dd43350e5" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_89beeb45-ca2d-4156-9259-b5ddf755a8ed" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_8905ec58-6b7b-4bb7-a9c3-8c142e4baf58" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_89beeb45-ca2d-4156-9259-b5ddf755a8ed" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_8905ec58-6b7b-4bb7-a9c3-8c142e4baf58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_8905ec58-6b7b-4bb7-a9c3-8c142e4baf58_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_8905ec58-6b7b-4bb7-a9c3-8c142e4baf58" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_8905ec58-6b7b-4bb7-a9c3-8c142e4baf58_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_9be39085-7e2b-4d41-b9a8-6fb1cdedffd4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_8905ec58-6b7b-4bb7-a9c3-8c142e4baf58" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_9be39085-7e2b-4d41-b9a8-6fb1cdedffd4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_34d51f87-8a48-4b22-9c3a-cb6265665726" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_9be39085-7e2b-4d41-b9a8-6fb1cdedffd4" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_34d51f87-8a48-4b22-9c3a-cb6265665726" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_69b2efff-ea44-43c9-aca7-ce72fb830c85" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_9be39085-7e2b-4d41-b9a8-6fb1cdedffd4" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_69b2efff-ea44-43c9-aca7-ce72fb830c85" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_91e41c6f-6f51-4e62-b853-55a46c2f75b3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_9be39085-7e2b-4d41-b9a8-6fb1cdedffd4" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_91e41c6f-6f51-4e62-b853-55a46c2f75b3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_62d7be5b-6810-4d23-95a1-707cdc9fc5c1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_89beeb45-ca2d-4156-9259-b5ddf755a8ed" xlink:to="loc_us-gaap_FinancialInstrumentAxis_62d7be5b-6810-4d23-95a1-707cdc9fc5c1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_62d7be5b-6810-4d23-95a1-707cdc9fc5c1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_62d7be5b-6810-4d23-95a1-707cdc9fc5c1" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_62d7be5b-6810-4d23-95a1-707cdc9fc5c1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_62d7be5b-6810-4d23-95a1-707cdc9fc5c1" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_0d6757eb-6c34-474f-8dde-3c39f6b5c195" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_0d6757eb-6c34-474f-8dde-3c39f6b5c195" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CanadianProvincialGovernmentsMember_9e74bbb2-54e9-430c-8f5d-5245f5edb6e0" xlink:href="rga-20240630.xsd#rga_CanadianProvincialGovernmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_rga_CanadianProvincialGovernmentsMember_9e74bbb2-54e9-430c-8f5d-5245f5edb6e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_4dee3dd1-9527-4f03-b79b-f7734e1b6200" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_4dee3dd1-9527-4f03-b79b-f7734e1b6200" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_8922ce39-9af6-474f-ac28-9e63ed47b0bd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_8922ce39-9af6-474f-ac28-9e63ed47b0bd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_99654681-b44d-4ab2-a2fb-1bc91ab2c3f1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_99654681-b44d-4ab2-a2fb-1bc91ab2c3f1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_32d89464-c2c5-42ca-9fa4-caef69cdd955" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_32d89464-c2c5-42ca-9fa4-caef69cdd955" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_41335615-979f-4b58-8a1c-a2aa2311ab7c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_41335615-979f-4b58-8a1c-a2aa2311ab7c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_dc10c35c-2375-4bfd-b723-93c1bfdcf71e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_dc10c35c-2375-4bfd-b723-93c1bfdcf71e" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_JapaneseGovernmentMember_44856285-2ab1-4c1c-a716-5044f1ec61e0" xlink:href="rga-20240630.xsd#rga_JapaneseGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_887735cf-975f-4e9e-8e97-dbdbde5db87b" xlink:to="loc_rga_JapaneseGovernmentMember_44856285-2ab1-4c1c-a716-5044f1ec61e0" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_db87cec0-8fb9-43e4-a6f9-c0adde69aa2e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_89beeb45-ca2d-4156-9259-b5ddf755a8ed" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_db87cec0-8fb9-43e4-a6f9-c0adde69aa2e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_db87cec0-8fb9-43e4-a6f9-c0adde69aa2e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_db87cec0-8fb9-43e4-a6f9-c0adde69aa2e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_db87cec0-8fb9-43e4-a6f9-c0adde69aa2e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_9c97dec8-efaa-4aef-9d3d-b9c855db418c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_db87cec0-8fb9-43e4-a6f9-c0adde69aa2e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_9c97dec8-efaa-4aef-9d3d-b9c855db418c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FairValueOptionContractholderDirectedUnitLinkedInvestmentsMember_76fcb7df-228b-4294-8e1c-d9b80305d881" xlink:href="rga-20240630.xsd#rga_FairValueOptionContractholderDirectedUnitLinkedInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_9c97dec8-efaa-4aef-9d3d-b9c855db418c" xlink:to="loc_rga_FairValueOptionContractholderDirectedUnitLinkedInvestmentsMember_76fcb7df-228b-4294-8e1c-d9b80305d881" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_OtherInvestedAssetsAxis_742a67b8-ddc7-4f9f-8760-2da3ea204add" xlink:href="rga-20240630.xsd#rga_OtherInvestedAssetsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_89beeb45-ca2d-4156-9259-b5ddf755a8ed" xlink:to="loc_rga_OtherInvestedAssetsAxis_742a67b8-ddc7-4f9f-8760-2da3ea204add" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_OtherInvestedAssetsDomain_742a67b8-ddc7-4f9f-8760-2da3ea204add_default" xlink:href="rga-20240630.xsd#rga_OtherInvestedAssetsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_OtherInvestedAssetsAxis_742a67b8-ddc7-4f9f-8760-2da3ea204add" xlink:to="loc_rga_OtherInvestedAssetsDomain_742a67b8-ddc7-4f9f-8760-2da3ea204add_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_OtherInvestedAssetsDomain_1c524b99-0dff-4af6-9585-ef03e18efc88" xlink:href="rga-20240630.xsd#rga_OtherInvestedAssetsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_OtherInvestedAssetsAxis_742a67b8-ddc7-4f9f-8760-2da3ea204add" xlink:to="loc_rga_OtherInvestedAssetsDomain_1c524b99-0dff-4af6-9585-ef03e18efc88" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCreditDerivativesMember_cb1b6880-365b-4ec1-aa6b-f5756005af1c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCreditDerivativesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_OtherInvestedAssetsDomain_1c524b99-0dff-4af6-9585-ef03e18efc88" xlink:to="loc_us-gaap_OtherCreditDerivativesMember_cb1b6880-365b-4ec1-aa6b-f5756005af1c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_900e92dc-c417-49e2-9ba9-e84dd43350e5" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_b315ffb6-c416-4a39-9128-45a15254938e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_b315ffb6-c416-4a39-9128-45a15254938e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentsFairValueDisclosure_6dbe05c8-1d5c-47c1-9fe9-08dabe1a857a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquityMethodInvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_us-gaap_EquityMethodInvestmentsFairValueDisclosure_6dbe05c8-1d5c-47c1-9fe9-08dabe1a857a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FairValueMeasuredOnRecurringBasisFundsHeldUnderReinsuranceAgreementsAssetEmbeddedDerivatives_52c80013-2867-4350-ae8a-4767681d2013" xlink:href="rga-20240630.xsd#rga_FairValueMeasuredOnRecurringBasisFundsHeldUnderReinsuranceAgreementsAssetEmbeddedDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_rga_FairValueMeasuredOnRecurringBasisFundsHeldUnderReinsuranceAgreementsAssetEmbeddedDerivatives_52c80013-2867-4350-ae8a-4767681d2013" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FundsHeldUnderReinsuranceAgreementsAssetFairValueDisclosure_1fa4ce82-99a5-4dda-90a4-4465fa2d064f" xlink:href="rga-20240630.xsd#rga_FundsHeldUnderReinsuranceAgreementsAssetFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_rga_FundsHeldUnderReinsuranceAgreementsAssetFairValueDisclosure_1fa4ce82-99a5-4dda-90a4-4465fa2d064f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_3d460165-2535-4621-9a92-3a44668708ef" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_3d460165-2535-4621-9a92-3a44668708ef" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FairValueMeasuredOnRecurringBasisShortTermInvestments_bd6db1e5-0ee4-4bcd-a9d7-098c15b169c1" xlink:href="rga-20240630.xsd#rga_FairValueMeasuredOnRecurringBasisShortTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_rga_FairValueMeasuredOnRecurringBasisShortTermInvestments_bd6db1e5-0ee4-4bcd-a9d7-098c15b169c1" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet_2e355fbb-3fc0-4df9-bcce-9f52979a88a3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet_2e355fbb-3fc0-4df9-bcce-9f52979a88a3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_648a5371-cbbd-446d-a416-106d409090d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_648a5371-cbbd-446d-a416-106d409090d6" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_267efffa-ff59-44ba-bd2e-6ad3d290dab9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_03e42892-074a-4d9d-977d-12e26200915d" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_267efffa-ff59-44ba-bd2e-6ad3d290dab9" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_00737c8f-93af-436e-bed2-41a2c196ae8a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_900e92dc-c417-49e2-9ba9-e84dd43350e5" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_00737c8f-93af-436e-bed2-41a2c196ae8a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FairValueMeasuredOnRecurringBasisGuaranteedInterestContractsEmbeddedDerivatives_ec80fa65-1a9b-4f53-8af7-e57a49122c0d" xlink:href="rga-20240630.xsd#rga_FairValueMeasuredOnRecurringBasisGuaranteedInterestContractsEmbeddedDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_00737c8f-93af-436e-bed2-41a2c196ae8a" xlink:to="loc_rga_FairValueMeasuredOnRecurringBasisGuaranteedInterestContractsEmbeddedDerivatives_ec80fa65-1a9b-4f53-8af7-e57a49122c0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsLiability_5a779143-5642-47e9-b582-97384912bdfc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FundsHeldUnderReinsuranceAgreementsLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_00737c8f-93af-436e-bed2-41a2c196ae8a" xlink:to="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsLiability_5a779143-5642-47e9-b582-97384912bdfc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesFairValueDisclosure_80c6b20a-1c29-4064-bae2-8e1bc6d0f495" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherLiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_00737c8f-93af-436e-bed2-41a2c196ae8a" xlink:to="loc_us-gaap_OtherLiabilitiesFairValueDisclosure_80c6b20a-1c29-4064-bae2-8e1bc6d0f495" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialLiabilitiesFairValueDisclosure_2275774f-ade8-4df0-abe0-06c44016f165" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialLiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_00737c8f-93af-436e-bed2-41a2c196ae8a" xlink:to="loc_us-gaap_FinancialLiabilitiesFairValueDisclosure_2275774f-ade8-4df0-abe0-06c44016f165" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueNetAssetLiability_b5471a5c-3a8d-4046-88ab-0d1ea257abd8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueNetAssetLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_900e92dc-c417-49e2-9ba9-e84dd43350e5" xlink:to="loc_us-gaap_FairValueNetAssetLiability_b5471a5c-3a8d-4046-88ab-0d1ea257abd8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_9cc6930c-6bc9-4685-9371-5f6d66eb445d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_900e92dc-c417-49e2-9ba9-e84dd43350e5" xlink:to="loc_us-gaap_DerivativeLiabilities_9cc6930c-6bc9-4685-9371-5f6d66eb445d" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesQuantitativeInformationforLevel3InputsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesQuantitativeInformationforLevel3InputsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesQuantitativeInformationforLevel3InputsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_bbd2da20-7187-44a8-afc9-6da1ce0d26c5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_f0170eae-1f81-4966-8c92-836e868999e5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_bbd2da20-7187-44a8-afc9-6da1ce0d26c5" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_f0170eae-1f81-4966-8c92-836e868999e5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_efa131fe-db90-41c2-9553-e14547183bed" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_f0170eae-1f81-4966-8c92-836e868999e5" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_efa131fe-db90-41c2-9553-e14547183bed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_efa131fe-db90-41c2-9553-e14547183bed_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_efa131fe-db90-41c2-9553-e14547183bed" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_efa131fe-db90-41c2-9553-e14547183bed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_68f89668-3a14-4b0d-85b5-cfd14a477332" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_efa131fe-db90-41c2-9553-e14547183bed" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_68f89668-3a14-4b0d-85b5-cfd14a477332" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_MeasurementInputCreditingRateMember_8cb2ba68-f81d-444a-a3e9-0df51f6ca798" xlink:href="rga-20240630.xsd#rga_MeasurementInputCreditingRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_68f89668-3a14-4b0d-85b5-cfd14a477332" xlink:to="loc_rga_MeasurementInputCreditingRateMember_8cb2ba68-f81d-444a-a3e9-0df51f6ca798" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputCounterpartyCreditRiskMember_0ac18534-a156-48b6-859a-1117998295e7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputCounterpartyCreditRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_68f89668-3a14-4b0d-85b5-cfd14a477332" xlink:to="loc_us-gaap_MeasurementInputCounterpartyCreditRiskMember_0ac18534-a156-48b6-859a-1117998295e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputWithdrawalRateMember_5a55b55d-455a-417a-8878-dd5437534cfc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputWithdrawalRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_68f89668-3a14-4b0d-85b5-cfd14a477332" xlink:to="loc_us-gaap_MeasurementInputWithdrawalRateMember_5a55b55d-455a-417a-8878-dd5437534cfc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputLapseRateMember_e5acb52a-5fc8-4db7-a2ce-8accef2ea0ff" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputLapseRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_68f89668-3a14-4b0d-85b5-cfd14a477332" xlink:to="loc_us-gaap_MeasurementInputLapseRateMember_e5acb52a-5fc8-4db7-a2ce-8accef2ea0ff" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputMortalityRateMember_aa1c8abf-49b4-428f-90f7-2d80b0d55205" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputMortalityRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_68f89668-3a14-4b0d-85b5-cfd14a477332" xlink:to="loc_us-gaap_MeasurementInputMortalityRateMember_aa1c8abf-49b4-428f-90f7-2d80b0d55205" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputEbitdaMultipleMember_ff4f8722-b26b-4f9e-8a1d-a0f4b7637f3a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MeasurementInputEbitdaMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_68f89668-3a14-4b0d-85b5-cfd14a477332" xlink:to="loc_us-gaap_MeasurementInputEbitdaMultipleMember_ff4f8722-b26b-4f9e-8a1d-a0f4b7637f3a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_b7bd7855-30f1-432d-9a2d-649dcd23fda4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_f0170eae-1f81-4966-8c92-836e868999e5" xlink:to="loc_us-gaap_FinancialInstrumentAxis_b7bd7855-30f1-432d-9a2d-649dcd23fda4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_b7bd7855-30f1-432d-9a2d-649dcd23fda4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_b7bd7855-30f1-432d-9a2d-649dcd23fda4" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_b7bd7855-30f1-432d-9a2d-649dcd23fda4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_b7bd7855-30f1-432d-9a2d-649dcd23fda4" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_96fb9db3-0880-4a09-8303-e8bda7e456ea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_96fb9db3-0880-4a09-8303-e8bda7e456ea" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_d5de780e-ca58-417c-ab8a-04b3da04a287" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_d5de780e-ca58-417c-ab8a-04b3da04a287" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_07e614ab-be44-4236-8bf9-0b306207585a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_07e614ab-be44-4236-8bf9-0b306207585a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_6f43fdc8-7f79-4143-959b-c1bf88dfb612" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:to="loc_us-gaap_EquitySecuritiesMember_6f43fdc8-7f79-4143-959b-c1bf88dfb612" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FundsWithheldAtInterestEmbeddedDerivativesMember_6bcbfa8a-af56-48c0-934f-7402618513bb" xlink:href="rga-20240630.xsd#rga_FundsWithheldAtInterestEmbeddedDerivativesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:to="loc_rga_FundsWithheldAtInterestEmbeddedDerivativesMember_6bcbfa8a-af56-48c0-934f-7402618513bb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_EmbeddedDerivativesInIndexedAnnuityMember_04a189e4-6774-4564-8a75-5c756b9331e0" xlink:href="rga-20240630.xsd#rga_EmbeddedDerivativesInIndexedAnnuityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:to="loc_rga_EmbeddedDerivativesInIndexedAnnuityMember_04a189e4-6774-4564-8a75-5c756b9331e0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_5b68da0e-9ffc-457e-97af-4ed73aef5197" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_6a1ca353-1f3f-4532-bf94-7673429a56fc" xlink:to="loc_us-gaap_CorporateAndOtherMember_5b68da0e-9ffc-457e-97af-4ed73aef5197" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_f862d57f-b02f-4774-b9df-d05ac74db6c8" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_f0170eae-1f81-4966-8c92-836e868999e5" xlink:to="loc_srt_RangeAxis_f862d57f-b02f-4774-b9df-d05ac74db6c8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_f862d57f-b02f-4774-b9df-d05ac74db6c8_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_f862d57f-b02f-4774-b9df-d05ac74db6c8" xlink:to="loc_srt_RangeMember_f862d57f-b02f-4774-b9df-d05ac74db6c8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_79ea8452-2f24-457c-8694-022aa5e0ba1b" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_f862d57f-b02f-4774-b9df-d05ac74db6c8" xlink:to="loc_srt_RangeMember_79ea8452-2f24-457c-8694-022aa5e0ba1b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_WeightedAverageMember_6b3c9fb7-ff62-4914-9023-df7279f59cdb" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_WeightedAverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_79ea8452-2f24-457c-8694-022aa5e0ba1b" xlink:to="loc_srt_WeightedAverageMember_6b3c9fb7-ff62-4914-9023-df7279f59cdb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_babdeb44-980f-4755-a25b-5398c9a04826" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_79ea8452-2f24-457c-8694-022aa5e0ba1b" xlink:to="loc_srt_MaximumMember_babdeb44-980f-4755-a25b-5398c9a04826" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_087f45fc-8465-4871-bcff-2a1a13c67912" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_79ea8452-2f24-457c-8694-022aa5e0ba1b" xlink:to="loc_srt_MinimumMember_087f45fc-8465-4871-bcff-2a1a13c67912" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_b4e30245-c9dc-43fe-9605-bb66f4db5c03" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_f0170eae-1f81-4966-8c92-836e868999e5" xlink:to="loc_us-gaap_ValuationTechniqueAxis_b4e30245-c9dc-43fe-9605-bb66f4db5c03" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_b4e30245-c9dc-43fe-9605-bb66f4db5c03_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_b4e30245-c9dc-43fe-9605-bb66f4db5c03" xlink:to="loc_us-gaap_ValuationTechniqueDomain_b4e30245-c9dc-43fe-9605-bb66f4db5c03_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_ced92709-699b-4ae2-bfdc-561c45f50f6d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_b4e30245-c9dc-43fe-9605-bb66f4db5c03" xlink:to="loc_us-gaap_ValuationTechniqueDomain_ced92709-699b-4ae2-bfdc-561c45f50f6d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeApproachValuationTechniqueMember_995e8c28-c41a-4aa8-9621-d170e00a995b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeApproachValuationTechniqueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_ced92709-699b-4ae2-bfdc-561c45f50f6d" xlink:to="loc_us-gaap_IncomeApproachValuationTechniqueMember_995e8c28-c41a-4aa8-9621-d170e00a995b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketApproachValuationTechniqueMember_605148eb-d0ff-4a80-b95c-d256d9147981" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MarketApproachValuationTechniqueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_ced92709-699b-4ae2-bfdc-561c45f50f6d" xlink:to="loc_us-gaap_MarketApproachValuationTechniqueMember_605148eb-d0ff-4a80-b95c-d256d9147981" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDiscountedCashFlowMember_49d2b63b-700b-4489-a29d-805477906979" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ValuationTechniqueDiscountedCashFlowMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_ced92709-699b-4ae2-bfdc-561c45f50f6d" xlink:to="loc_us-gaap_ValuationTechniqueDiscountedCashFlowMember_49d2b63b-700b-4489-a29d-805477906979" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentMeasurementInput_52d3aeaf-5045-42cb-bcf3-2117e4bf0867" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_bbd2da20-7187-44a8-afc9-6da1ce0d26c5" xlink:to="loc_us-gaap_DebtInstrumentMeasurementInput_52d3aeaf-5045-42cb-bcf3-2117e4bf0867" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_ac4a1263-ba80-4a94-843e-f1af31822444" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_bbd2da20-7187-44a8-afc9-6da1ce0d26c5" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_ac4a1263-ba80-4a94-843e-f1af31822444" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_37c98191-00cb-4345-8a31-3e1897215cb3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_bbd2da20-7187-44a8-afc9-6da1ce0d26c5" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_37c98191-00cb-4345-8a31-3e1897215cb3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNiMeasurementInput_f7e5b3c8-0c2e-43d0-91b8-8cc9293249a4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquitySecuritiesFvNiMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_bbd2da20-7187-44a8-afc9-6da1ce0d26c5" xlink:to="loc_us-gaap_EquitySecuritiesFvNiMeasurementInput_f7e5b3c8-0c2e-43d0-91b8-8cc9293249a4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmbeddedDerivativeAssetMeasurementInput_a9f6a580-d14d-4574-8f2e-54c3c8f7dc1c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmbeddedDerivativeAssetMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_bbd2da20-7187-44a8-afc9-6da1ce0d26c5" xlink:to="loc_us-gaap_EmbeddedDerivativeAssetMeasurementInput_a9f6a580-d14d-4574-8f2e-54c3c8f7dc1c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmbeddedDerivativeLiabilityMeasurementInput_66610467-e82c-44d2-a086-8ed2bb0aa50a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EmbeddedDerivativeLiabilityMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_bbd2da20-7187-44a8-afc9-6da1ce0d26c5" xlink:to="loc_us-gaap_EmbeddedDerivativeLiabilityMeasurementInput_66610467-e82c-44d2-a086-8ed2bb0aa50a" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesChangesinLevel3AssetsandLiabilitiesDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesChangesinLevel3AssetsandLiabilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesChangesinLevel3AssetsandLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_bbfa0b74-9e45-46d0-a4e1-d40a871b5a50" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_53f6da23-80eb-4cca-8789-8a21d80455bc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_bbfa0b74-9e45-46d0-a4e1-d40a871b5a50" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_53f6da23-80eb-4cca-8789-8a21d80455bc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FairValueByMajorCategoryAxis_076dc393-111d-4006-86e2-3d11dcad6ee3" xlink:href="rga-20240630.xsd#rga_FairValueByMajorCategoryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_53f6da23-80eb-4cca-8789-8a21d80455bc" xlink:to="loc_rga_FairValueByMajorCategoryAxis_076dc393-111d-4006-86e2-3d11dcad6ee3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FairValueByMajorCategoryDomain_076dc393-111d-4006-86e2-3d11dcad6ee3_default" xlink:href="rga-20240630.xsd#rga_FairValueByMajorCategoryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_rga_FairValueByMajorCategoryAxis_076dc393-111d-4006-86e2-3d11dcad6ee3" xlink:to="loc_rga_FairValueByMajorCategoryDomain_076dc393-111d-4006-86e2-3d11dcad6ee3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FairValueByMajorCategoryDomain_2132102c-c711-47bc-b78b-465dd1531806" xlink:href="rga-20240630.xsd#rga_FairValueByMajorCategoryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_rga_FairValueByMajorCategoryAxis_076dc393-111d-4006-86e2-3d11dcad6ee3" xlink:to="loc_rga_FairValueByMajorCategoryDomain_2132102c-c711-47bc-b78b-465dd1531806" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableforsaleSecuritiesMember_1716a12b-6235-4351-aaf0-c332e5894f70" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AvailableforsaleSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_rga_FairValueByMajorCategoryDomain_2132102c-c711-47bc-b78b-465dd1531806" xlink:to="loc_us-gaap_AvailableforsaleSecuritiesMember_1716a12b-6235-4351-aaf0-c332e5894f70" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_92ebfd29-7a9b-4dfc-b2b7-51807f38dc1d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_53f6da23-80eb-4cca-8789-8a21d80455bc" xlink:to="loc_us-gaap_FinancialInstrumentAxis_92ebfd29-7a9b-4dfc-b2b7-51807f38dc1d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_92ebfd29-7a9b-4dfc-b2b7-51807f38dc1d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_92ebfd29-7a9b-4dfc-b2b7-51807f38dc1d" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_92ebfd29-7a9b-4dfc-b2b7-51807f38dc1d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_92ebfd29-7a9b-4dfc-b2b7-51807f38dc1d" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_ebd5b2c3-0d91-45d1-bbae-a4df17e1ba4c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_ebd5b2c3-0d91-45d1-bbae-a4df17e1ba4c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CanadianProvincialGovernmentsMember_31b1bd13-8a58-4d88-9572-3bda461c8768" xlink:href="rga-20240630.xsd#rga_CanadianProvincialGovernmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_rga_CanadianProvincialGovernmentsMember_31b1bd13-8a58-4d88-9572-3bda461c8768" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_2a24b739-2396-42af-a9af-0101dcc71107" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_2a24b739-2396-42af-a9af-0101dcc71107" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_2756202e-9439-47c8-98f0-03ada5344f3e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_2756202e-9439-47c8-98f0-03ada5344f3e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_fafe3a64-eb8a-4311-8b8f-b7f6ae6e1855" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_fafe3a64-eb8a-4311-8b8f-b7f6ae6e1855" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_faa08b44-8f9f-4635-aca0-28dad3977451" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_faa08b44-8f9f-4635-aca0-28dad3977451" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_f4f5cefc-d21d-404d-98d3-f1f2093f09d3" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_f4f5cefc-d21d-404d-98d3-f1f2093f09d3" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_a839960b-a2a8-4888-b6d3-d803a1e96d9c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_a839960b-a2a8-4888-b6d3-d803a1e96d9c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_b6361a1e-b375-4d64-b7fb-310d9faf6fb8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_b6361a1e-b375-4d64-b7fb-310d9faf6fb8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FundsWithheldAtInterestEmbeddedDerivativesMember_bce99e2e-6941-4813-8959-5c9244239ece" xlink:href="rga-20240630.xsd#rga_FundsWithheldAtInterestEmbeddedDerivativesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_rga_FundsWithheldAtInterestEmbeddedDerivativesMember_bce99e2e-6941-4813-8959-5c9244239ece" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestmentsMember_9b820c40-2372-47dc-a404-5c018a0f44b9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShortTermInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_ShortTermInvestmentsMember_9b820c40-2372-47dc-a404-5c018a0f44b9" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember_b79674cf-cd54-49e3-bc5c-db6cdf397d63" xlink:href="rga-20240630.xsd#rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember_b79674cf-cd54-49e3-bc5c-db6cdf397d63" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_e17bde73-819b-4bd2-a832-2ad56f75e8cb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_EquitySecuritiesMember_e17bde73-819b-4bd2-a832-2ad56f75e8cb" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StructuredFinanceMember_ae529267-1609-4f9e-b5c4-d7b84cedf6e7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StructuredFinanceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_StructuredFinanceMember_ae529267-1609-4f9e-b5c4-d7b84cedf6e7" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_FundsWithheldAtInterestMember_be574c33-3465-453c-b1ff-d0fcb2c4fccf" xlink:href="rga-20240630.xsd#rga_FundsWithheldAtInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_rga_FundsWithheldAtInterestMember_be574c33-3465-453c-b1ff-d0fcb2c4fccf" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashEquivalentsMember_39d9135c-9c1b-4aef-9fcc-c9195446a903" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_97c636da-70d8-4355-b5a0-087272c72157" xlink:to="loc_us-gaap_CashEquivalentsMember_39d9135c-9c1b-4aef-9fcc-c9195446a903" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_f1c316bb-0de1-4c8d-a993-92c3393eb827" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_53f6da23-80eb-4cca-8789-8a21d80455bc" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_f1c316bb-0de1-4c8d-a993-92c3393eb827" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_f1c316bb-0de1-4c8d-a993-92c3393eb827_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_f1c316bb-0de1-4c8d-a993-92c3393eb827" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_f1c316bb-0de1-4c8d-a993-92c3393eb827_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_b72b8386-689b-4c75-9de6-2cf4be581e0d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_f1c316bb-0de1-4c8d-a993-92c3393eb827" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_b72b8386-689b-4c75-9de6-2cf4be581e0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeMember_b2945b31-54d3-48f5-af2c-24e4f9f7b2b6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InvestmentIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_b72b8386-689b-4c75-9de6-2cf4be581e0d" xlink:to="loc_us-gaap_InvestmentIncomeMember_b2945b31-54d3-48f5-af2c-24e4f9f7b2b6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeMember_fcef7646-6d3e-4024-87c4-e2d813c0cbc1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_b72b8386-689b-4c75-9de6-2cf4be581e0d" xlink:to="loc_us-gaap_InterestIncomeMember_fcef7646-6d3e-4024-87c4-e2d813c0cbc1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_InvestmentRelatedGainsLossesMember_c048c3f7-49cb-468d-838d-2981f69d5cb9" xlink:href="rga-20240630.xsd#rga_InvestmentRelatedGainsLossesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_b72b8386-689b-4c75-9de6-2cf4be581e0d" xlink:to="loc_rga_InvestmentRelatedGainsLossesMember_c048c3f7-49cb-468d-838d-2981f69d5cb9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeMember_da0d4ade-55bd-4bf2-b2fb-801cefd8fed7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_b72b8386-689b-4c75-9de6-2cf4be581e0d" xlink:to="loc_us-gaap_OtherComprehensiveIncomeMember_da0d4ade-55bd-4bf2-b2fb-801cefd8fed7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_bbfa0b74-9e45-46d0-a4e1-d40a871b5a50" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_90d76403-3513-42b3-940a-5af5781fd761" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_90d76403-3513-42b3-940a-5af5781fd761" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_049d3c56-f8d5-4b5b-a461-4d67f27ba088" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_049d3c56-f8d5-4b5b-a461-4d67f27ba088" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_c822aab5-081d-4830-aaae-9723f3961a45" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_c822aab5-081d-4830-aaae-9723f3961a45" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_e9b4f917-a382-49e9-a442-a75cf6e928a6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_e9b4f917-a382-49e9-a442-a75cf6e928a6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_eb259ff2-b30a-4720-8754-e1d43e2690d8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_eb259ff2-b30a-4720-8754-e1d43e2690d8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales_67abfa9e-6d20-4061-88a0-63f84c36b595" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales_67abfa9e-6d20-4061-88a0-63f84c36b595" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_811cee77-0a4a-4680-8cc8-7d9251bdd2e1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_811cee77-0a4a-4680-8cc8-7d9251bdd2e1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3_e1e6aa80-a27d-4802-8405-0877c7b9a69c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3_e1e6aa80-a27d-4802-8405-0877c7b9a69c" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_fe95ac9b-78a5-4c43-b620-1578cb001335" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_a24f97b1-ac63-4888-818a-c5b738d6376e" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_fe95ac9b-78a5-4c43-b620-1578cb001335" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_d0e55bc6-7ce3-40a8-8fc2-b34a15a5cf43" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_bbfa0b74-9e45-46d0-a4e1-d40a871b5a50" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_8429b5ea-3394-40ee-b6da-1c3b080cf2d1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_8429b5ea-3394-40ee-b6da-1c3b080cf2d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_231aba97-9a68-4158-ac1a-535d2b919fde" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_231aba97-9a68-4158-ac1a-535d2b919fde" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome_14b90d22-b5bf-4436-bb8b-5bb650d7dd13" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome_14b90d22-b5bf-4436-bb8b-5bb650d7dd13" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases_de079ced-2647-4a0a-8ad9-3a2c7b504e72" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases_de079ced-2647-4a0a-8ad9-3a2c7b504e72" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_3aa2b2c6-526c-444e-83ad-6e2293c457c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_3aa2b2c6-526c-444e-83ad-6e2293c457c9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3_8fcc13ad-ec54-45e3-ae00-78d2f0ab2db7" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3_8fcc13ad-ec54-45e3-ae00-78d2f0ab2db7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3_a00b0532-2d56-4b3d-be3c-60a647b550aa" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_1ade583c-b8fa-4f38-a125-4ccbf7d17298" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3_a00b0532-2d56-4b3d-be3c-60a647b550aa" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_f22a518c-e06d-4b5a-bfab-14fe591427c2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_bbfa0b74-9e45-46d0-a4e1-d40a871b5a50" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_f22a518c-e06d-4b5a-bfab-14fe591427c2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_3daa089c-ed39-4e0c-9dbd-19e4ed93afea" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_bbfa0b74-9e45-46d0-a4e1-d40a871b5a50" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_3daa089c-ed39-4e0c-9dbd-19e4ed93afea" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesFinancialInstrumentswhereCarryingAmountsandFairValuesMayDifferDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesFinancialInstrumentswhereCarryingAmountsandFairValuesMayDifferDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FairValueofAssetsandLiabilitiesFairValueofAssetsandLiabilitiesFinancialInstrumentswhereCarryingAmountsandFairValuesMayDifferDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_23975eaa-256b-414c-a9bd-f1086cf111d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByBalanceSheetGroupingTable_b819958c-78de-41f7-a06d-b858f6cfefb5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByBalanceSheetGroupingTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_23975eaa-256b-414c-a9bd-f1086cf111d6" xlink:to="loc_us-gaap_FairValueByBalanceSheetGroupingTable_b819958c-78de-41f7-a06d-b858f6cfefb5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_4ae5082d-283b-4294-9557-0ae676d23ff2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_b819958c-78de-41f7-a06d-b858f6cfefb5" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_4ae5082d-283b-4294-9557-0ae676d23ff2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_4ae5082d-283b-4294-9557-0ae676d23ff2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_4ae5082d-283b-4294-9557-0ae676d23ff2" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_4ae5082d-283b-4294-9557-0ae676d23ff2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_7fa2646a-5179-4cc0-961e-1a44f8693611" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_4ae5082d-283b-4294-9557-0ae676d23ff2" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_7fa2646a-5179-4cc0-961e-1a44f8693611" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_a1e2501a-51d4-4323-83bf-0b2cc0fdd70a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_7fa2646a-5179-4cc0-961e-1a44f8693611" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_a1e2501a-51d4-4323-83bf-0b2cc0fdd70a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_d283d223-62e7-4372-bce2-ea2eafcef3f9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_7fa2646a-5179-4cc0-961e-1a44f8693611" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_d283d223-62e7-4372-bce2-ea2eafcef3f9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_8340e432-5fdf-477e-8a1f-a69bfc0e4098" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_7fa2646a-5179-4cc0-961e-1a44f8693611" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_8340e432-5fdf-477e-8a1f-a69bfc0e4098" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4e0a002c-b11f-47ec-8942-e8bc60a0add8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_b819958c-78de-41f7-a06d-b858f6cfefb5" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4e0a002c-b11f-47ec-8942-e8bc60a0add8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4e0a002c-b11f-47ec-8942-e8bc60a0add8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4e0a002c-b11f-47ec-8942-e8bc60a0add8" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4e0a002c-b11f-47ec-8942-e8bc60a0add8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b7c10737-d213-462f-9d5b-3c521a6d7456" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4e0a002c-b11f-47ec-8942-e8bc60a0add8" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b7c10737-d213-462f-9d5b-3c521a6d7456" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_203a91b6-7d6e-43cf-b85d-bcc80ee77218" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b7c10737-d213-462f-9d5b-3c521a6d7456" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_203a91b6-7d6e-43cf-b85d-bcc80ee77218" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_e1c25b1a-98e4-462c-8501-bc94fe07285c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b7c10737-d213-462f-9d5b-3c521a6d7456" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_e1c25b1a-98e4-462c-8501-bc94fe07285c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_81eec175-deb5-4ceb-9d5c-b49e1a108464" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_b7c10737-d213-462f-9d5b-3c521a6d7456" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_81eec175-deb5-4ceb-9d5c-b49e1a108464" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_23975eaa-256b-414c-a9bd-f1086cf111d6" xlink:to="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet_9e84f225-b113-47b4-99a7-2d5c40e0593c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:to="loc_us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet_9e84f225-b113-47b4-99a7-2d5c40e0593c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansInsurancePolicy_65ffd22b-0c3a-43cf-966b-b08d8fcf0822" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LoansInsurancePolicy"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:to="loc_us-gaap_LoansInsurancePolicy_65ffd22b-0c3a-43cf-966b-b08d8fcf0822" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsAsset_0c9a25b5-d88b-4488-a417-506e70fceadb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FundsHeldUnderReinsuranceAgreementsAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:to="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsAsset_0c9a25b5-d88b-4488-a417-506e70fceadb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_7c9323c4-f269-485d-b16f-672ed54f299d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_7c9323c4-f269-485d-b16f-672ed54f299d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherShortTermInvestments_500b70a2-133a-4203-9f77-7435617fbef8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherShortTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:to="loc_us-gaap_OtherShortTermInvestments_500b70a2-133a-4203-9f77-7435617fbef8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInvestments_6472fc82-6ea4-47bb-aa9f-bd79f2895951" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:to="loc_us-gaap_OtherInvestments_6472fc82-6ea4-47bb-aa9f-bd79f2895951" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedInvestmentIncomeReceivable_76e9e26c-4ec0-43e6-a858-62d135ab8157" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AccruedInvestmentIncomeReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:to="loc_us-gaap_AccruedInvestmentIncomeReceivable_76e9e26c-4ec0-43e6-a858-62d135ab8157" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateInvestmentsUnconsolidatedRealEstateAndOtherJointVentures_bb15219a-3929-4ce7-97d4-6bf52ea9f90d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RealEstateInvestmentsUnconsolidatedRealEstateAndOtherJointVentures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_876a0071-d238-4ddf-8b35-6da1c8c56ffc" xlink:to="loc_us-gaap_RealEstateInvestmentsUnconsolidatedRealEstateAndOtherJointVentures_bb15219a-3929-4ce7-97d4-6bf52ea9f90d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAbstract_14f08b20-e7de-4cd4-a099-b9ce8e525ff4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_23975eaa-256b-414c-a9bd-f1086cf111d6" xlink:to="loc_us-gaap_LiabilitiesAbstract_14f08b20-e7de-4cd4-a099-b9ce8e525ff4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteedInterestContracts_5e5e2ca7-0d5f-4759-be0c-7fd5e602f69e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteedInterestContracts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_14f08b20-e7de-4cd4-a099-b9ce8e525ff4" xlink:to="loc_us-gaap_GuaranteedInterestContracts_5e5e2ca7-0d5f-4759-be0c-7fd5e602f69e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsLiability_89d72479-ba50-47e6-8faa-b13c50594dbb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FundsHeldUnderReinsuranceAgreementsLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_14f08b20-e7de-4cd4-a099-b9ce8e525ff4" xlink:to="loc_us-gaap_FundsHeldUnderReinsuranceAgreementsLiability_89d72479-ba50-47e6-8faa-b13c50594dbb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_f220f4df-ac77-4085-ae4b-ba85d25a5b76" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_14f08b20-e7de-4cd4-a099-b9ce8e525ff4" xlink:to="loc_us-gaap_LongTermDebt_f220f4df-ac77-4085-ae4b-ba85d25a5b76" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_51b455e9-e3c3-4c96-b59b-8dc12ed2d492" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_14f08b20-e7de-4cd4-a099-b9ce8e525ff4" xlink:to="loc_us-gaap_LongTermDebtFairValue_51b455e9-e3c3-4c96-b59b-8dc12ed2d492" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceRecoverablesGross_8a324f38-da06-4fd1-b075-ad7d27dcd830" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReinsuranceRecoverablesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_23975eaa-256b-414c-a9bd-f1086cf111d6" xlink:to="loc_us-gaap_ReinsuranceRecoverablesGross_8a324f38-da06-4fd1-b075-ad7d27dcd830" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/EmployeeBenefitPlansDefinedBenefitPlansDisclosureDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#EmployeeBenefitPlansDefinedBenefitPlansDisclosureDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/EmployeeBenefitPlansDefinedBenefitPlansDisclosureDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0b115dd7-546b-45dd-8ac8-9d6b3216f248" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_b19b5d30-157e-455e-9fd8-0f26733127ec" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0b115dd7-546b-45dd-8ac8-9d6b3216f248" xlink:to="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_b19b5d30-157e-455e-9fd8-0f26733127ec" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_27e43939-022c-4af9-9a09-b3341c760ee8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetirementPlanTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_b19b5d30-157e-455e-9fd8-0f26733127ec" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_27e43939-022c-4af9-9a09-b3341c760ee8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_27e43939-022c-4af9-9a09-b3341c760ee8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_27e43939-022c-4af9-9a09-b3341c760ee8" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_27e43939-022c-4af9-9a09-b3341c760ee8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_906c84c9-d383-4531-8faa-4328cab11dba" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_27e43939-022c-4af9-9a09-b3341c760ee8" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_906c84c9-d383-4531-8faa-4328cab11dba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PensionPlansDefinedBenefitMember_ce82f12a-c989-4fb3-bba7-15fba21c079b" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PensionPlansDefinedBenefitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_906c84c9-d383-4531-8faa-4328cab11dba" xlink:to="loc_us-gaap_PensionPlansDefinedBenefitMember_ce82f12a-c989-4fb3-bba7-15fba21c079b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_7cba6fbf-7726-4026-b659-672b11b01bd9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_906c84c9-d383-4531-8faa-4328cab11dba" xlink:to="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_7cba6fbf-7726-4026-b659-672b11b01bd9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost_3acdfb8c-a671-4bf1-9bb0-3777af0ade11" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanServiceCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0b115dd7-546b-45dd-8ac8-9d6b3216f248" xlink:to="loc_us-gaap_DefinedBenefitPlanServiceCost_3acdfb8c-a671-4bf1-9bb0-3777af0ade11" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost_0349f61f-7286-4f66-944b-706ed45ee83e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanInterestCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0b115dd7-546b-45dd-8ac8-9d6b3216f248" xlink:to="loc_us-gaap_DefinedBenefitPlanInterestCost_0349f61f-7286-4f66-944b-706ed45ee83e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_12e7e75b-5387-45ce-9dd1-74659fb3429d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0b115dd7-546b-45dd-8ac8-9d6b3216f248" xlink:to="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_12e7e75b-5387-45ce-9dd1-74659fb3429d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_be9b06ed-c22a-478c-b5e9-6e422243c4be" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0b115dd7-546b-45dd-8ac8-9d6b3216f248" xlink:to="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_be9b06ed-c22a-478c-b5e9-6e422243c4be" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_f0d7e215-b576-40ad-8487-5d7a06afa87d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0b115dd7-546b-45dd-8ac8-9d6b3216f248" xlink:to="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_f0d7e215-b576-40ad-8487-5d7a06afa87d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_a7cc87a3-0e3a-4336-b6d9-8612f96ddef9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0b115dd7-546b-45dd-8ac8-9d6b3216f248" xlink:to="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_a7cc87a3-0e3a-4336-b6d9-8612f96ddef9" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/CommitmentsContingenciesandGuaranteesCommitmentstoFundInvestmentsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#CommitmentsContingenciesandGuaranteesCommitmentstoFundInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/CommitmentsContingenciesandGuaranteesCommitmentstoFundInvestmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems_3f65cf9b-b03e-44d5-9696-c7912f413e01" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable_c2de0393-a356-4625-a5e7-bcaa5e7eeb28" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems_3f65cf9b-b03e-44d5-9696-c7912f413e01" xlink:to="loc_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable_c2de0393-a356-4625-a5e7-bcaa5e7eeb28" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_bc797b69-e11d-4a80-9f98-5923dffe288e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable_c2de0393-a356-4625-a5e7-bcaa5e7eeb28" xlink:to="loc_us-gaap_FinancialInstrumentAxis_bc797b69-e11d-4a80-9f98-5923dffe288e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_bc797b69-e11d-4a80-9f98-5923dffe288e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_bc797b69-e11d-4a80-9f98-5923dffe288e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_bc797b69-e11d-4a80-9f98-5923dffe288e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7c5694af-b177-4c20-874b-a474036e90af" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_bc797b69-e11d-4a80-9f98-5923dffe288e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7c5694af-b177-4c20-874b-a474036e90af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LimitedPartnerMember_095fc864-2b7e-427e-886c-1f2678cbb426" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LimitedPartnerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7c5694af-b177-4c20-874b-a474036e90af" xlink:to="loc_us-gaap_LimitedPartnerMember_095fc864-2b7e-427e-886c-1f2678cbb426" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialLoanMember_0c6a0e5e-5b6b-4447-8bf3-3cbfd05db56d" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommercialLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7c5694af-b177-4c20-874b-a474036e90af" xlink:to="loc_us-gaap_CommercialLoanMember_0c6a0e5e-5b6b-4447-8bf3-3cbfd05db56d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankLoanObligationsMember_128eb1d8-d645-4ea7-a059-7f95f7a2072e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_BankLoanObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7c5694af-b177-4c20-874b-a474036e90af" xlink:to="loc_us-gaap_BankLoanObligationsMember_128eb1d8-d645-4ea7-a059-7f95f7a2072e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_EquityReleaseMortgagesMember_8915db93-116d-4da3-b39a-c7c3de2957d0" xlink:href="rga-20240630.xsd#rga_EquityReleaseMortgagesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_7c5694af-b177-4c20-874b-a474036e90af" xlink:to="loc_rga_EquityReleaseMortgagesMember_8915db93-116d-4da3-b39a-c7c3de2957d0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability_3475506b-f711-464f-8d55-6740cd1c0c22" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems_3f65cf9b-b03e-44d5-9696-c7912f413e01" xlink:to="loc_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability_3475506b-f711-464f-8d55-6740cd1c0c22" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/CommitmentsContingenciesandGuaranteesMaximumPotentialObligationDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#CommitmentsContingenciesandGuaranteesMaximumPotentialObligationDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/CommitmentsContingenciesandGuaranteesMaximumPotentialObligationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsLineItems_5f976bfa-0cf1-43ae-ba9a-dfca1213e8ae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsTable_db720c29-5da0-4ae1-a2c8-f2362c6377c9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_5f976bfa-0cf1-43ae-ba9a-dfca1213e8ae" xlink:to="loc_us-gaap_OtherCommitmentsTable_db720c29-5da0-4ae1-a2c8-f2362c6377c9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsAxis_f8bb11ed-7cda-46ad-bff6-0a9c5f72fda6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OtherCommitmentsTable_db720c29-5da0-4ae1-a2c8-f2362c6377c9" xlink:to="loc_us-gaap_OtherCommitmentsAxis_f8bb11ed-7cda-46ad-bff6-0a9c5f72fda6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsDomain_f8bb11ed-7cda-46ad-bff6-0a9c5f72fda6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_OtherCommitmentsAxis_f8bb11ed-7cda-46ad-bff6-0a9c5f72fda6" xlink:to="loc_us-gaap_OtherCommitmentsDomain_f8bb11ed-7cda-46ad-bff6-0a9c5f72fda6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_OtherCommitmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_OtherCommitmentsAxis_f8bb11ed-7cda-46ad-bff6-0a9c5f72fda6" xlink:to="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandThirtyFourMember_2eb7e4e3-853f-476c-9c55-b64a24e40ee8" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandThirtyFourMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandThirtyFourMember_2eb7e4e3-853f-476c-9c55-b64a24e40ee8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandThirtyFiveMember_997bdaef-a492-4051-9eb3-fa91f620a1e8" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandThirtyFiveMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandThirtyFiveMember_997bdaef-a492-4051-9eb3-fa91f620a1e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandThirtySixMember_b9fea9e5-9568-4953-ba9b-fddbb03f2d6f" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandThirtySixMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandThirtySixMember_b9fea9e5-9568-4953-ba9b-fddbb03f2d6f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandThirtySevenMember_e0252c84-7ea1-42dc-914b-5bacd636f88b" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandThirtySevenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandThirtySevenMember_e0252c84-7ea1-42dc-914b-5bacd636f88b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandThirtyEightMember_31f0dce5-ed0e-49ab-9849-40ede3738b25" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandThirtyEightMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandThirtyEightMember_31f0dce5-ed0e-49ab-9849-40ede3738b25" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandThirtyNineMember_7a81f97c-881f-484c-ac53-386f86317cb4" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandThirtyNineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandThirtyNineMember_7a81f97c-881f-484c-ac53-386f86317cb4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandFortySixMember_4a626c14-f5be-4948-9b45-a5c738988989" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandFortySixMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandFortySixMember_4a626c14-f5be-4948-9b45-a5c738988989" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandFortyOneMember_d1177322-4a66-4272-bb61-d9cfccf0e446" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandFortyOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandFortyOneMember_d1177322-4a66-4272-bb61-d9cfccf0e446" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_CommitmentPeriodTwoThousandFortyNineMember_5d227563-bf1c-4acf-887a-f8e3364a8f12" xlink:href="rga-20240630.xsd#rga_CommitmentPeriodTwoThousandFortyNineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_055ee70e-5071-4a07-b8e2-6f125c9a204c" xlink:to="loc_rga_CommitmentPeriodTwoThousandFortyNineMember_5d227563-bf1c-4acf-887a-f8e3364a8f12" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsMaximumExposure_6002e2ef-5982-4a81-87fc-90c1ef949bf0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsMaximumExposure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_5f976bfa-0cf1-43ae-ba9a-dfca1213e8ae" xlink:to="loc_us-gaap_GuaranteeObligationsMaximumExposure_6002e2ef-5982-4a81-87fc-90c1ef949bf0" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/CommitmentsContingenciesandGuaranteesGuaranteesIssuedDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#CommitmentsContingenciesandGuaranteesGuaranteesIssuedDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/CommitmentsContingenciesandGuaranteesGuaranteesIssuedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsLineItems_c9f5fdd7-f8b1-4c08-a219-a66117f34d80" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_e998ec21-22ec-4734-ba12-971ed4ef4d95" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ScheduleOfGuaranteeObligationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_c9f5fdd7-f8b1-4c08-a219-a66117f34d80" xlink:to="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_e998ec21-22ec-4734-ba12-971ed4ef4d95" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsByNatureAxis_49229bb6-6ed4-438d-93de-67c4ddf953b0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsByNatureAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_e998ec21-22ec-4734-ba12-971ed4ef4d95" xlink:to="loc_us-gaap_GuaranteeObligationsByNatureAxis_49229bb6-6ed4-438d-93de-67c4ddf953b0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain_49229bb6-6ed4-438d-93de-67c4ddf953b0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis_49229bb6-6ed4-438d-93de-67c4ddf953b0" xlink:to="loc_us-gaap_GuaranteeObligationsNatureDomain_49229bb6-6ed4-438d-93de-67c4ddf953b0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain_ab06836a-ccd4-4162-abed-7d3ad9ba9680" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_GuaranteeObligationsNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis_49229bb6-6ed4-438d-93de-67c4ddf953b0" xlink:to="loc_us-gaap_GuaranteeObligationsNatureDomain_ab06836a-ccd4-4162-abed-7d3ad9ba9680" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/SegmentInformationTotalRevenuesofReportableSegmentsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#SegmentInformationTotalRevenuesofReportableSegmentsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/SegmentInformationTotalRevenuesofReportableSegmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_d6638c48-5a3e-4ba1-a288-11c6ca2fb41a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentReportingRevenueReconcilingItemLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_f21c6ea0-6c12-49e5-8866-c154ff411d06" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_d6638c48-5a3e-4ba1-a288-11c6ca2fb41a" xlink:to="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_f21c6ea0-6c12-49e5-8866-c154ff411d06" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_f8677b42-ee96-477b-8b5a-fd0c6f77421d" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_f21c6ea0-6c12-49e5-8866-c154ff411d06" xlink:to="loc_srt_ProductOrServiceAxis_f8677b42-ee96-477b-8b5a-fd0c6f77421d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_f8677b42-ee96-477b-8b5a-fd0c6f77421d_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_f8677b42-ee96-477b-8b5a-fd0c6f77421d" xlink:to="loc_srt_ProductsAndServicesDomain_f8677b42-ee96-477b-8b5a-fd0c6f77421d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_3b7659e0-8bd9-4fea-987c-7f45cb2d29b5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_f8677b42-ee96-477b-8b5a-fd0c6f77421d" xlink:to="loc_srt_ProductsAndServicesDomain_3b7659e0-8bd9-4fea-987c-7f45cb2d29b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_b325cfce-68e6-48eb-b15d-301f6e988715" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_3b7659e0-8bd9-4fea-987c-7f45cb2d29b5" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_b325cfce-68e6-48eb-b15d-301f6e988715" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NontraditionalLongDurationContractsMember_d42dae3b-c0b4-4ba3-90a7-ca39399e191c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NontraditionalLongDurationContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_3b7659e0-8bd9-4fea-987c-7f45cb2d29b5" xlink:to="loc_us-gaap_NontraditionalLongDurationContractsMember_d42dae3b-c0b4-4ba3-90a7-ca39399e191c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_35bb9d14-720d-4243-bd7d-be9b3dd24fc8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_f21c6ea0-6c12-49e5-8866-c154ff411d06" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_35bb9d14-720d-4243-bd7d-be9b3dd24fc8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_35bb9d14-720d-4243-bd7d-be9b3dd24fc8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_35bb9d14-720d-4243-bd7d-be9b3dd24fc8" xlink:to="loc_us-gaap_SegmentDomain_35bb9d14-720d-4243-bd7d-be9b3dd24fc8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_82d4ae0b-d3d2-4b1a-b23e-c198c2646bce" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_35bb9d14-720d-4243-bd7d-be9b3dd24fc8" xlink:to="loc_us-gaap_SegmentDomain_82d4ae0b-d3d2-4b1a-b23e-c198c2646bce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_4472ab76-fe97-4acc-89e5-4ba949206320" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_82d4ae0b-d3d2-4b1a-b23e-c198c2646bce" xlink:to="loc_us-gaap_AllOtherSegmentsMember_4472ab76-fe97-4acc-89e5-4ba949206320" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_f5bdf117-a76d-4abd-b30d-a474a6e8e0c5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_82d4ae0b-d3d2-4b1a-b23e-c198c2646bce" xlink:to="loc_us-gaap_CorporateAndOtherMember_f5bdf117-a76d-4abd-b30d-a474a6e8e0c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_401d2739-9f39-4a97-a6eb-d287a4f14df4" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_f21c6ea0-6c12-49e5-8866-c154ff411d06" xlink:to="loc_srt_StatementGeographicalAxis_401d2739-9f39-4a97-a6eb-d287a4f14df4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_401d2739-9f39-4a97-a6eb-d287a4f14df4_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_401d2739-9f39-4a97-a6eb-d287a4f14df4" xlink:to="loc_srt_SegmentGeographicalDomain_401d2739-9f39-4a97-a6eb-d287a4f14df4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_ced2e169-a759-48f9-8893-dcf2c8c66899" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_401d2739-9f39-4a97-a6eb-d287a4f14df4" xlink:to="loc_srt_SegmentGeographicalDomain_ced2e169-a759-48f9-8893-dcf2c8c66899" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_023259c4-74b4-447c-9cfb-f566d3331660" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ced2e169-a759-48f9-8893-dcf2c8c66899" xlink:to="loc_srt_AmericasMember_023259c4-74b4-447c-9cfb-f566d3331660" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_995980aa-852c-441d-9732-86abf2ba7d17" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ced2e169-a759-48f9-8893-dcf2c8c66899" xlink:to="loc_country_CA_995980aa-852c-441d-9732-86abf2ba7d17" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_21a3077d-eee9-45f3-b4c8-dc4755f305ab" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ced2e169-a759-48f9-8893-dcf2c8c66899" xlink:to="loc_us-gaap_EMEAMember_21a3077d-eee9-45f3-b4c8-dc4755f305ab" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_9b801e84-bca6-4e01-8f04-a994b4e658d7" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_ced2e169-a759-48f9-8893-dcf2c8c66899" xlink:to="loc_srt_AsiaPacificMember_9b801e84-bca6-4e01-8f04-a994b4e658d7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_f7c0ee14-2d06-4bbe-9964-1b9be56e3936" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Revenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_d6638c48-5a3e-4ba1-a288-11c6ca2fb41a" xlink:to="loc_us-gaap_Revenues_f7c0ee14-2d06-4bbe-9964-1b9be56e3936" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/SegmentInformationIncomeLossBeforeProvisionforIncomeTaxofReportableSegmentsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#SegmentInformationIncomeLossBeforeProvisionforIncomeTaxofReportableSegmentsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/SegmentInformationIncomeLossBeforeProvisionforIncomeTaxofReportableSegmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_6d547430-4447-4120-8340-3c7d218f0565" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_b4fc3e84-49e6-499d-ba84-543ff9d339a1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_6d547430-4447-4120-8340-3c7d218f0565" xlink:to="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_b4fc3e84-49e6-499d-ba84-543ff9d339a1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_4078ddf2-3e34-4a3d-a337-3b6432abc82e" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_b4fc3e84-49e6-499d-ba84-543ff9d339a1" xlink:to="loc_srt_ProductOrServiceAxis_4078ddf2-3e34-4a3d-a337-3b6432abc82e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_4078ddf2-3e34-4a3d-a337-3b6432abc82e_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_4078ddf2-3e34-4a3d-a337-3b6432abc82e" xlink:to="loc_srt_ProductsAndServicesDomain_4078ddf2-3e34-4a3d-a337-3b6432abc82e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_caf5bde2-7195-407c-99dc-455ae850b0fb" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_4078ddf2-3e34-4a3d-a337-3b6432abc82e" xlink:to="loc_srt_ProductsAndServicesDomain_caf5bde2-7195-407c-99dc-455ae850b0fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_c7cdb984-bbcb-4f97-9e31-5c6d56d60a37" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_caf5bde2-7195-407c-99dc-455ae850b0fb" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_c7cdb984-bbcb-4f97-9e31-5c6d56d60a37" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NontraditionalLongDurationContractsMember_a36d3020-70ae-4e41-b634-91960b98c31c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NontraditionalLongDurationContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_caf5bde2-7195-407c-99dc-455ae850b0fb" xlink:to="loc_us-gaap_NontraditionalLongDurationContractsMember_a36d3020-70ae-4e41-b634-91960b98c31c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_bcc88b04-5b52-4d1d-b1e4-365e10a3b89c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_b4fc3e84-49e6-499d-ba84-543ff9d339a1" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_bcc88b04-5b52-4d1d-b1e4-365e10a3b89c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_bcc88b04-5b52-4d1d-b1e4-365e10a3b89c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_bcc88b04-5b52-4d1d-b1e4-365e10a3b89c" xlink:to="loc_us-gaap_SegmentDomain_bcc88b04-5b52-4d1d-b1e4-365e10a3b89c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_47eff725-a7b3-46ee-829d-443bb591fa84" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_bcc88b04-5b52-4d1d-b1e4-365e10a3b89c" xlink:to="loc_us-gaap_SegmentDomain_47eff725-a7b3-46ee-829d-443bb591fa84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_f9d3ff5a-cfa0-4993-8a04-0357dcfc7207" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_47eff725-a7b3-46ee-829d-443bb591fa84" xlink:to="loc_us-gaap_CorporateAndOtherMember_f9d3ff5a-cfa0-4993-8a04-0357dcfc7207" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_91b5f2ab-3b17-4e3e-819c-5f7c44d9ad75" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_47eff725-a7b3-46ee-829d-443bb591fa84" xlink:to="loc_us-gaap_AllOtherSegmentsMember_91b5f2ab-3b17-4e3e-819c-5f7c44d9ad75" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_520096da-7bf1-431b-8e65-477927d3249d" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_b4fc3e84-49e6-499d-ba84-543ff9d339a1" xlink:to="loc_srt_StatementGeographicalAxis_520096da-7bf1-431b-8e65-477927d3249d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_520096da-7bf1-431b-8e65-477927d3249d_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_520096da-7bf1-431b-8e65-477927d3249d" xlink:to="loc_srt_SegmentGeographicalDomain_520096da-7bf1-431b-8e65-477927d3249d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_a581edaa-bd4a-442d-ae17-c6fe29479dd2" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_520096da-7bf1-431b-8e65-477927d3249d" xlink:to="loc_srt_SegmentGeographicalDomain_a581edaa-bd4a-442d-ae17-c6fe29479dd2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_c4c415e1-1e7b-459a-8433-0afe7a3e4987" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a581edaa-bd4a-442d-ae17-c6fe29479dd2" xlink:to="loc_srt_AmericasMember_c4c415e1-1e7b-459a-8433-0afe7a3e4987" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_d3d36a5c-09cf-4d60-9199-73a70efabed1" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a581edaa-bd4a-442d-ae17-c6fe29479dd2" xlink:to="loc_country_CA_d3d36a5c-09cf-4d60-9199-73a70efabed1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_c7810d9c-670f-43f2-9bf6-389a0d934ffb" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a581edaa-bd4a-442d-ae17-c6fe29479dd2" xlink:to="loc_us-gaap_EMEAMember_c7810d9c-670f-43f2-9bf6-389a0d934ffb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_a7332c05-6198-4d5b-9c8e-c3b6d61eccfe" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_a581edaa-bd4a-442d-ae17-c6fe29479dd2" xlink:to="loc_srt_AsiaPacificMember_a7332c05-6198-4d5b-9c8e-c3b6d61eccfe" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_6c126fab-b084-451f-9d92-21351f5ab145" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_6d547430-4447-4120-8340-3c7d218f0565" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_6c126fab-b084-451f-9d92-21351f5ab145" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/SegmentInformationTotalAssetsofReportableSegmentsDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#SegmentInformationTotalAssetsofReportableSegmentsDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/SegmentInformationTotalAssetsofReportableSegmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingAssetReconcilingItemLineItems_231c4d93-16ff-4f88-b1d1-af74dbb88101" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentReportingAssetReconcilingItemLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable_b55bef82-481a-4ebe-9acd-0cb7cbefa1f4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingAssetReconcilingItemLineItems_231c4d93-16ff-4f88-b1d1-af74dbb88101" xlink:to="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable_b55bef82-481a-4ebe-9acd-0cb7cbefa1f4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_1eec7d0b-12e8-4091-a292-9f30cd56f933" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable_b55bef82-481a-4ebe-9acd-0cb7cbefa1f4" xlink:to="loc_srt_ProductOrServiceAxis_1eec7d0b-12e8-4091-a292-9f30cd56f933" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_1eec7d0b-12e8-4091-a292-9f30cd56f933_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_1eec7d0b-12e8-4091-a292-9f30cd56f933" xlink:to="loc_srt_ProductsAndServicesDomain_1eec7d0b-12e8-4091-a292-9f30cd56f933_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_ac8b6929-8244-4b0a-a3fb-26962795fbde" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_1eec7d0b-12e8-4091-a292-9f30cd56f933" xlink:to="loc_srt_ProductsAndServicesDomain_ac8b6929-8244-4b0a-a3fb-26962795fbde" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LifeInsuranceSegmentMember_5351375a-fed6-4392-b7b3-0872c66b5465" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LifeInsuranceSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_ac8b6929-8244-4b0a-a3fb-26962795fbde" xlink:to="loc_us-gaap_LifeInsuranceSegmentMember_5351375a-fed6-4392-b7b3-0872c66b5465" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NontraditionalLongDurationContractsMember_83ce1c8d-af7c-4c65-93fe-eb4a47629c0e" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_NontraditionalLongDurationContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_ac8b6929-8244-4b0a-a3fb-26962795fbde" xlink:to="loc_us-gaap_NontraditionalLongDurationContractsMember_83ce1c8d-af7c-4c65-93fe-eb4a47629c0e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_1dc92141-060d-4c65-82db-e4a8531c2fd2" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable_b55bef82-481a-4ebe-9acd-0cb7cbefa1f4" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_1dc92141-060d-4c65-82db-e4a8531c2fd2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_1dc92141-060d-4c65-82db-e4a8531c2fd2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_1dc92141-060d-4c65-82db-e4a8531c2fd2" xlink:to="loc_us-gaap_SegmentDomain_1dc92141-060d-4c65-82db-e4a8531c2fd2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_b7b89c24-176a-4c50-8db7-07660ff1d9e0" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_1dc92141-060d-4c65-82db-e4a8531c2fd2" xlink:to="loc_us-gaap_SegmentDomain_b7b89c24-176a-4c50-8db7-07660ff1d9e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_664220da-4712-4fca-8703-bcc7dfb640f8" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_b7b89c24-176a-4c50-8db7-07660ff1d9e0" xlink:to="loc_us-gaap_CorporateAndOtherMember_664220da-4712-4fca-8703-bcc7dfb640f8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_f0a89293-209d-48bf-b78e-057e232eef14" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_b7b89c24-176a-4c50-8db7-07660ff1d9e0" xlink:to="loc_us-gaap_AllOtherSegmentsMember_f0a89293-209d-48bf-b78e-057e232eef14" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_2d5d94c6-c0d8-4a6f-b59f-71d482ec6426" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable_b55bef82-481a-4ebe-9acd-0cb7cbefa1f4" xlink:to="loc_srt_StatementGeographicalAxis_2d5d94c6-c0d8-4a6f-b59f-71d482ec6426" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_2d5d94c6-c0d8-4a6f-b59f-71d482ec6426_default" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_2d5d94c6-c0d8-4a6f-b59f-71d482ec6426" xlink:to="loc_srt_SegmentGeographicalDomain_2d5d94c6-c0d8-4a6f-b59f-71d482ec6426_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_8b83f68a-7d5a-4f9b-99df-b259bbffe8c0" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_2d5d94c6-c0d8-4a6f-b59f-71d482ec6426" xlink:to="loc_srt_SegmentGeographicalDomain_8b83f68a-7d5a-4f9b-99df-b259bbffe8c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_49188aba-cba5-4fde-9e06-2d46797f28a9" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_8b83f68a-7d5a-4f9b-99df-b259bbffe8c0" xlink:to="loc_srt_AmericasMember_49188aba-cba5-4fde-9e06-2d46797f28a9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_e5539252-3b4b-47d3-8922-4b9e1c9c5cf1" xlink:href="https://xbrl.sec.gov/country/2024/country-2024.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_8b83f68a-7d5a-4f9b-99df-b259bbffe8c0" xlink:to="loc_country_CA_e5539252-3b4b-47d3-8922-4b9e1c9c5cf1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_f5d80aaa-e013-4660-9986-a31e551cf303" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_8b83f68a-7d5a-4f9b-99df-b259bbffe8c0" xlink:to="loc_us-gaap_EMEAMember_f5d80aaa-e013-4660-9986-a31e551cf303" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_cb380c7a-cd11-4687-89c4-9ea23e1d38d5" xlink:href="https://xbrl.fasb.org/srt/2024/elts/srt-2024.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_8b83f68a-7d5a-4f9b-99df-b259bbffe8c0" xlink:to="loc_srt_AsiaPacificMember_cb380c7a-cd11-4687-89c4-9ea23e1d38d5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_aa83e83b-8ed5-4311-8ea7-81e5af15f7ac" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingAssetReconcilingItemLineItems_231c4d93-16ff-4f88-b1d1-af74dbb88101" xlink:to="loc_us-gaap_Assets_aa83e83b-8ed5-4311-8ea7-81e5af15f7ac" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.rgare.com/role/FinancingActivitiesDetails" xlink:type="simple" xlink:href="rga-20240630.xsd#FinancingActivitiesDetails"/>
  <link:definitionLink xlink:role="http://www.rgare.com/role/FinancingActivitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_1abdeee7-0afd-45e7-a0ef-a0fe6bf627ae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_b963b3e1-03c0-4af2-aecc-050967b1362a" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1abdeee7-0afd-45e7-a0ef-a0fe6bf627ae" xlink:to="loc_us-gaap_DebtInstrumentTable_b963b3e1-03c0-4af2-aecc-050967b1362a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_8414838f-c69f-4f4d-b49b-b18ec955caae" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_b963b3e1-03c0-4af2-aecc-050967b1362a" xlink:to="loc_us-gaap_DebtInstrumentAxis_8414838f-c69f-4f4d-b49b-b18ec955caae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_8414838f-c69f-4f4d-b49b-b18ec955caae_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_8414838f-c69f-4f4d-b49b-b18ec955caae" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_8414838f-c69f-4f4d-b49b-b18ec955caae_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1d590e54-aaef-4462-9528-f66670861dc4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_8414838f-c69f-4f4d-b49b-b18ec955caae" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1d590e54-aaef-4462-9528-f66670861dc4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_rga_SeniorNote2034Member_a22c2357-e4ca-4a71-ab98-8b10ccd4b941" xlink:href="rga-20240630.xsd#rga_SeniorNote2034Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1d590e54-aaef-4462-9528-f66670861dc4" xlink:to="loc_rga_SeniorNote2034Member_a22c2357-e4ca-4a71-ab98-8b10ccd4b941" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_a2a4235b-5574-4d77-803b-b2c581dbf3c1" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_b963b3e1-03c0-4af2-aecc-050967b1362a" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_a2a4235b-5574-4d77-803b-b2c581dbf3c1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_a2a4235b-5574-4d77-803b-b2c581dbf3c1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_a2a4235b-5574-4d77-803b-b2c581dbf3c1" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_a2a4235b-5574-4d77-803b-b2c581dbf3c1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_62507cee-e39b-42da-824c-9846403a853f" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_a2a4235b-5574-4d77-803b-b2c581dbf3c1" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_62507cee-e39b-42da-824c-9846403a853f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_e42bab26-276a-48a9-84a6-72ce37559486" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_62507cee-e39b-42da-824c-9846403a853f" xlink:to="loc_us-gaap_SeniorNotesMember_e42bab26-276a-48a9-84a6-72ce37559486" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_4849d1d9-9567-4ac4-b036-8a3a2fd55bf5" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1abdeee7-0afd-45e7-a0ef-a0fe6bf627ae" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_4849d1d9-9567-4ac4-b036-8a3a2fd55bf5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_eea1a0d9-7790-4b84-975b-3042891e78b4" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1abdeee7-0afd-45e7-a0ef-a0fe6bf627ae" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_eea1a0d9-7790-4b84-975b-3042891e78b4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts_b362d62c-e235-4aa3-ab24-e1ad95dcc6d6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1abdeee7-0afd-45e7-a0ef-a0fe6bf627ae" xlink:to="loc_us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts_b362d62c-e235-4aa3-ab24-e1ad95dcc6d6" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/AwardTypeOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2024/ecd-2024.xsd#AwardTypeOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/ecd/AwardTypeOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_us-gaap_PerformanceSharesMember" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember" xlink:type="arc" order="4"/>
  </link:definitionLink>
</link:linkbase>