<?xml version="1.0" encoding="utf-8"?>
<linkbase xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:xbrldt="http://xbrl.org/2005/xbrldt">
  <!-- INTEGIX by Ez-XBRL -->
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <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"/>
  <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"/>
  <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"/>
  <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"/>
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/notAll" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#notAll"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ConsolidatedStatementsOfChangesInEquity" roleURI="http://www.metallaroyalty.com/role/ConsolidatedStatementsOfChangesInEquity"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#RoyaltyStreamAndOtherInterestsTables" roleURI="http://www.metallaroyalty.com/role/RoyaltyStreamAndOtherInterestsTables"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#RoyaltyStreamAndOtherInterestsNarrativeDetails" roleURI="http://www.metallaroyalty.com/role/RoyaltyStreamAndOtherInterestsNarrativeDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#InvestmentInSilverbackNarrativeDetails" roleURI="http://www.metallaroyalty.com/role/InvestmentInSilverbackNarrativeDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#LoansPayableNarrativeDetails" roleURI="http://www.metallaroyalty.com/role/LoansPayableNarrativeDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#RELATEDPARTYTRANSACTIONSANDBALANCESDetails1" roleURI="http://www.metallaroyalty.com/role/RELATEDPARTYTRANSACTIONSANDBALANCESDetails1"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#SupplementalDisclosureWithRespectToCashFlowsNarrativeDetails" roleURI="http://www.metallaroyalty.com/role/SupplementalDisclosureWithRespectToCashFlowsNarrativeDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#FinancialInstrumentsNarrativeDetails" roleURI="http://www.metallaroyalty.com/role/FinancialInstrumentsNarrativeDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#EventsAfterReportingDateNarrativeDetails" roleURI="http://www.metallaroyalty.com/role/EventsAfterReportingDateNarrativeDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfDetailedInformationAboutRoyaltyInterestsAndDeferredAcquisitionCostsDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfDetailedInformationAboutRoyaltyInterestsAndDeferredAcquisitionCostsDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfDetailedInformationAboutPurchasePriceAllocationForAcquisitionDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfDetailedInformationAboutPurchasePriceAllocationForAcquisitionDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfTransactionsRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombinationDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfTransactionsRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombinationDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfSubsidiaryDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfSubsidiaryDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfDetailedInformationAboutLoansPayableDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfDetailedInformationAboutLoansPayableDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfDeferredIncomeTaxAssetLiabilityDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfDeferredIncomeTaxAssetLiabilityDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfRangeOfExercisePricesOfOutstandingShareOptionsDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfRangeOfExercisePricesOfOutstandingShareOptionsDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfRangeOfExercisePricesOfOutstandingWarrantsDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfRangeOfExercisePricesOfOutstandingWarrantsDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfTransactionsBetweenRelatedPartiesDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfTransactionsBetweenRelatedPartiesDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfSignificantTemporaryDifferencesUnusedTaxCreditsAndUnusedTaxLossesDetails" roleURI="http://www.metallaroyalty.com/role/ScheduleOfSignificantTemporaryDifferencesUnusedTaxCreditsAndUnusedTaxLossesDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#REVENUEDetails" roleURI="http://www.metallaroyalty.com/role/REVENUEDetails"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#ScheduleOfInformationRelatedToContractualObligationsDetail" roleURI="http://www.metallaroyalty.com/role/ScheduleOfInformationRelatedToContractualObligationsDetail"/>
  <roleRef xlink:type="simple" xlink:href="mtaff-20200531.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESDetails" roleURI="http://www.metallaroyalty.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESDetails"/>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ConsolidatedStatementsOfChangesInEquity">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_StatementOfChangesInEquityLineItems" xlink:label="loc_ifrs-full_StatementOfChangesInEquityLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_StatementOfChangesInEquityTable" xlink:label="loc_ifrs-full_StatementOfChangesInEquityTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ComponentsOfEquityAxis" xlink:label="loc_ifrs-full_ComponentsOfEquityAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EquityMember" xlink:label="loc_ifrs-full_EquityMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IssuedCapitalMember" xlink:label="loc_ifrs-full_IssuedCapitalMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_OtherReservesMember" xlink:label="loc_ifrs-full_OtherReservesMember_2"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_RetainedEarningsMember" xlink:label="loc_ifrs-full_RetainedEarningsMember_3"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EquityMember" xlink:label="loc_ifrs-full_EquityMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_Equity" xlink:label="loc_ifrs-full_Equity_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NumberOfSharesOutstanding" xlink:label="loc_ifrs-full_NumberOfSharesOutstanding_9"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyInterests" xlink:label="loc_mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyInterests_10"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests" xlink:label="loc_mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests_11"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughPrivatePlacementsAndShareIssuances" xlink:label="loc_mtaff_IncreaseDecreaseThroughPrivatePlacementsAndShareIssuances_12"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughPrivatePlacementsAndShareIssuancesShares" xlink:label="loc_mtaff_IncreaseDecreaseThroughPrivatePlacementsAndShareIssuancesShares_13"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ShareIssueRelatedCost" xlink:label="loc_ifrs-full_ShareIssueRelatedCost_14"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_FindersWarrantsShareIssueRelatedCosts" xlink:label="loc_mtaff_FindersWarrantsShareIssueRelatedCosts_15"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyAndStreamInterest" xlink:label="loc_mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyAndStreamInterest_16"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyAndStreamInterestsInShares" xlink:label="loc_mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyAndStreamInterestsInShares_17"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments_18"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable" xlink:label="loc_mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable_19"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IncreaseDecreaseThroughExerciseOfOptions" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughExerciseOfOptions_20"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughExerciseOfOptionsShares" xlink:label="loc_mtaff_IncreaseDecreaseThroughExerciseOfOptionsShares_21"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IncreaseDecreaseThroughExerciseOfWarrantsEquity" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughExerciseOfWarrantsEquity_22"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughExerciseOfWarrantsEquityInShares" xlink:label="loc_mtaff_IncreaseDecreaseThroughExerciseOfWarrantsEquityInShares_23"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions_24"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValueOfRestrictedStockUnitIssuedToDirectorsAndOfficers" xlink:label="loc_mtaff_ValueOfRestrictedStockUnitIssuedToDirectorsAndOfficers_25"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RestrictedStockUnitIssuedToDirectorsAndOfficers" xlink:label="loc_mtaff_RestrictedStockUnitIssuedToDirectorsAndOfficers_26"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseLoansPayableThroughIssuedOfWarrants" xlink:label="loc_mtaff_IncreaseDecreaseLoansPayableThroughIssuedOfWarrants_27"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughAllocationOfConversionFeature" xlink:label="loc_mtaff_IncreaseDecreaseThroughAllocationOfConversionFeature_28"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation" xlink:label="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation_29"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_FindersShareIssueRelatedCosts" xlink:label="loc_mtaff_FindersShareIssueRelatedCosts_30"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseInDeferredAcquisitionCosts" xlink:label="loc_mtaff_IncreaseDecreaseInDeferredAcquisitionCosts_31"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesWarrantsIssuedAsDeferredAcquisitionCosts" xlink:label="loc_mtaff_NumberOfCommonSharesWarrantsIssuedAsDeferredAcquisitionCosts_32"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactions" xlink:label="loc_mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactions_33"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactionsInShare" xlink:label="loc_mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactionsInShare_34"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DividendsRecognisedAsDistributionsToOwnersOfParent" xlink:label="loc_ifrs-full_DividendsRecognisedAsDistributionsToOwnersOfParent_35"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ProfitLoss" xlink:label="loc_ifrs-full_ProfitLoss_36"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_StatementOfChangesInEquityTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_StatementOfChangesInEquityTable_1" xlink:to="loc_ifrs-full_ComponentsOfEquityAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ComponentsOfEquityAxis_1" xlink:to="loc_ifrs-full_EquityMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_1" xlink:to="loc_ifrs-full_IssuedCapitalMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_1" xlink:to="loc_ifrs-full_OtherReservesMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EquityMember_1" xlink:to="loc_ifrs-full_RetainedEarningsMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ComponentsOfEquityAxis_1" xlink:to="loc_ifrs-full_EquityMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_Equity_8" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_NumberOfSharesOutstanding_9" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyInterests_10" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests_11" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughPrivatePlacementsAndShareIssuances_12" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughPrivatePlacementsAndShareIssuancesShares_13" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_ShareIssueRelatedCost_14" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_FindersWarrantsShareIssueRelatedCosts_15" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyAndStreamInterest_16" order="90" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughAcquisitionOfRoyaltyAndStreamInterestsInShares_17" order="100" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments_18" order="110" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable_19" order="120" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughExerciseOfOptions_20" order="130" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughExerciseOfOptionsShares_21" order="140" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughExerciseOfWarrantsEquity_22" order="150" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughExerciseOfWarrantsEquityInShares_23" order="160" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughSharebasedPaymentTransactions_24" order="170" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_ValueOfRestrictedStockUnitIssuedToDirectorsAndOfficers_25" order="180" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_RestrictedStockUnitIssuedToDirectorsAndOfficers_26" order="190" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseLoansPayableThroughIssuedOfWarrants_27" order="200" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughAllocationOfConversionFeature_28" order="210" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation_29" order="220" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_FindersShareIssueRelatedCosts_30" order="230" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseInDeferredAcquisitionCosts_31" order="240" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesWarrantsIssuedAsDeferredAcquisitionCosts_32" order="250" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactions_33" order="260" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactionsInShare_34" order="270" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_DividendsRecognisedAsDistributionsToOwnersOfParent_35" order="280" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_StatementOfChangesInEquityLineItems_0" xlink:to="loc_ifrs-full_ProfitLoss_36" order="290" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/RoyaltyStreamAndOtherInterestsTables">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems" xlink:label="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable" xlink:label="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BusinessCombinationsAxis" xlink:label="loc_ifrs-full_BusinessCombinationsAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IdahoResourcesCorpAcquisitionMember" xlink:label="loc_mtaff_IdahoResourcesCorpAcquisitionMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValgoldAcquisitionsMember" xlink:label="loc_mtaff_ValgoldAcquisitionsMember_2"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfDetailedInformationAboutRoyaltyInterestsAndDeferredAcquisitionCostsExplanatoryTextBlock" xlink:label="loc_mtaff_DisclosureOfDetailedInformationAboutRoyaltyInterestsAndDeferredAcquisitionCostsExplanatoryTextBlock_7"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfDetailedInformationAboutPurchasePriceAllocationForAcquisitionExplanatoryTextBlock" xlink:label="loc_mtaff_DisclosureOfDetailedInformationAboutPurchasePriceAllocationForAcquisitionExplanatoryTextBlock_8"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_ifrs-full_BusinessCombinationsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_IdahoResourcesCorpAcquisitionMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_ValgoldAcquisitionsMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_DisclosureOfDetailedInformationAboutRoyaltyInterestsAndDeferredAcquisitionCostsExplanatoryTextBlock_7" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_DisclosureOfDetailedInformationAboutPurchasePriceAllocationForAcquisitionExplanatoryTextBlock_8" order="20" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/RoyaltyStreamAndOtherInterestsNarrativeDetails">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems" xlink:label="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable" xlink:label="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BusinessCombinationsAxis" xlink:label="loc_ifrs-full_BusinessCombinationsAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IdahoResourcesCorpAcquisitionMember" xlink:label="loc_mtaff_IdahoResourcesCorpAcquisitionMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NuevaUnionAcquisitionMember" xlink:label="loc_mtaff_NuevaUnionAcquisitionMember_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AlamosAcquisitionsMember" xlink:label="loc_mtaff_AlamosAcquisitionsMember_3"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TowerMountainAcquisitionMember" xlink:label="loc_mtaff_TowerMountainAcquisitionMember_4"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_FifteenMileStreamAcquisitionsMember" xlink:label="loc_mtaff_FifteenMileStreamAcquisitionsMember_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DufferinEastAcquisitionMember" xlink:label="loc_mtaff_DufferinEastAcquisitionMember_6"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CapOesteSurEastAcquisitionMember" xlink:label="loc_mtaff_CapOesteSurEastAcquisitionMember_7"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SantaGertrudisAcquisitionsMember" xlink:label="loc_mtaff_SantaGertrudisAcquisitionsMember_8"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValgoldAcquisitionsMember" xlink:label="loc_mtaff_ValgoldAcquisitionsMember_9"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AkasabaWestAcquisitionMember" xlink:label="loc_mtaff_AkasabaWestAcquisitionMember_10"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CategoriesOfRelatedPartiesAxis" xlink:label="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_14"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_14"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AgnicoEagleMinesLimitedMember" xlink:label="loc_mtaff_AgnicoEagleMinesLimitedMember_14"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_MiradoMineProjectMember" xlink:label="loc_mtaff_MiradoMineProjectMember_15"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_MineraTritonArgentinaMember" xlink:label="loc_mtaff_MineraTritonArgentinaMember_16"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_GarrisonProjectNsrMember" xlink:label="loc_mtaff_GarrisonProjectNsrMember_17"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LosPlatosProjectNsrMember" xlink:label="loc_mtaff_LosPlatosProjectNsrMember_18"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TypesOfInvestmentPropertyAxis" xlink:label="loc_ifrs-full_TypesOfInvestmentPropertyAxis_22"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_InvestmentPropertyMember" xlink:label="loc_ifrs-full_InvestmentPropertyMember_22"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_JoaquinProjectMember" xlink:label="loc_mtaff_JoaquinProjectMember_22"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ZarumaGoldMineMember" xlink:label="loc_mtaff_ZarumaGoldMineMember_23"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PuchuldizaProjectMember" xlink:label="loc_mtaff_PuchuldizaProjectMember_24"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_HolyePondExtensionPropertyMember" xlink:label="loc_mtaff_HolyePondExtensionPropertyMember_25"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_MontclergPropertyMember" xlink:label="loc_mtaff_MontclergPropertyMember_26"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_WestTimminsExtensionPropertiesMember" xlink:label="loc_mtaff_WestTimminsExtensionPropertiesMember_27"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DesantisPropertiesMember" xlink:label="loc_mtaff_DesantisPropertiesMember_28"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_EitherHoylePondMineOrWestTimminsMineMember" xlink:label="loc_mtaff_EitherHoylePondMineOrWestTimminsMineMember_29"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TowerMountainProjectMember" xlink:label="loc_mtaff_TowerMountainProjectMember_30"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_InvestmentPropertyMember" xlink:label="loc_ifrs-full_InvestmentPropertyMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis" xlink:label="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis_34"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain" xlink:label="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_34"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AngloZekeNsrMember" xlink:label="loc_mtaff_AngloZekeNsrMember_34"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RedHillNsrMember" xlink:label="loc_mtaff_RedHillNsrMember_35"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_BiricuNsrMember" xlink:label="loc_mtaff_BiricuNsrMember_36"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_WasamacNsrMember" xlink:label="loc_mtaff_WasamacNsrMember_37"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ElRealitoNsrMember" xlink:label="loc_mtaff_ElRealitoNsrMember_38"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LaFortunaNsrOptionMember" xlink:label="loc_mtaff_LaFortunaNsrOptionMember_39"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain" xlink:label="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConditionsAxis" xlink:label="loc_mtaff_ConditionsAxis_43"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConditionsDomain" xlink:label="loc_mtaff_ConditionsDomain_43"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConditionOneMember" xlink:label="loc_mtaff_ConditionOneMember_43"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConditionTwoMember" xlink:label="loc_mtaff_ConditionTwoMember_44"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConditionsThreeMember" xlink:label="loc_mtaff_ConditionsThreeMember_45"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConditionsDomain" xlink:label="loc_mtaff_ConditionsDomain_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CashTransferred" xlink:label="loc_ifrs-full_CashTransferred_50"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EquityInterestsOfAcquirer" xlink:label="loc_ifrs-full_EquityInterestsOfAcquirer_51"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests" xlink:label="loc_mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests_52"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SharePricePerShare" xlink:label="loc_mtaff_SharePricePerShare_53"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ResultOfIndependentMineralResourceEstimationReport" xlink:label="loc_mtaff_ResultOfIndependentMineralResourceEstimationReport_54"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ProceedsFromSaleOfProject" xlink:label="loc_mtaff_ProceedsFromSaleOfProject_55"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NetSmelterReturnAcquiredPercentage" xlink:label="loc_mtaff_NetSmelterReturnAcquiredPercentage_56"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PurchasePriceOfAgreement" xlink:label="loc_mtaff_PurchasePriceOfAgreement_57"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PurchasePriceOfAgreementPayableInShares" xlink:label="loc_mtaff_PurchasePriceOfAgreementPayableInShares_58"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PercentageOfCashAndCommonSharesPay" xlink:label="loc_mtaff_PercentageOfCashAndCommonSharesPay_59"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CashAndCommonSharesPaid" xlink:label="loc_mtaff_CashAndCommonSharesPaid_60"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CashFlowsUsedForAcquisitionsOfRoyaltyAndStreamInterests" xlink:label="loc_mtaff_CashFlowsUsedForAcquisitionsOfRoyaltyAndStreamInterests_61"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PurchasePriceOfAcquisitionPaidInCash" xlink:label="loc_mtaff_PurchasePriceOfAcquisitionPaidInCash_62"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AcquisitionCostsForRoyaltyInterests" xlink:label="loc_mtaff_AcquisitionCostsForRoyaltyInterests_63"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NetSmelterReturn" xlink:label="loc_mtaff_NetSmelterReturn_64"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_PaymentsForShareIssueCosts" xlink:label="loc_ifrs-full_PaymentsForShareIssueCosts_65"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesReceivedForExchangeRatio" xlink:label="loc_mtaff_NumberOfCommonSharesReceivedForExchangeRatio_66"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExemptionOnGoldProduced" xlink:label="loc_mtaff_ExemptionOnGoldProduced_67"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_BuyBackRightPercentage" xlink:label="loc_mtaff_BuyBackRightPercentage_68"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_HalfOfNetSmelterReturnAcquiredPercentage" xlink:label="loc_mtaff_HalfOfNetSmelterReturnAcquiredPercentage_69"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RightToBuyBackStreamAmount" xlink:label="loc_mtaff_RightToBuyBackStreamAmount_70"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfRoyaltyInterest" xlink:label="loc_mtaff_NumberOfRoyaltyInterest_71"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfSilverStreamInterests" xlink:label="loc_mtaff_NumberOfSilverStreamInterests_72"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConvertibleDebenturePayable" xlink:label="loc_mtaff_ConvertibleDebenturePayable_73"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RoyaltyInterestsAndDeferredAcquisitionCosts" xlink:label="loc_mtaff_RoyaltyInterestsAndDeferredAcquisitionCosts_74"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_OperatingCostContributionPricePerOunce" xlink:label="loc_mtaff_OperatingCostContributionPricePerOunce_75"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PercentageIncrementsOfExceededSilverPricePerOunce" xlink:label="loc_mtaff_PercentageIncrementsOfExceededSilverPricePerOunce_76"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PercentageRightToBuySilverProduction" xlink:label="loc_mtaff_PercentageRightToBuySilverProduction_77"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExceedingSilverPricePerOunce" xlink:label="loc_mtaff_ExceedingSilverPricePerOunce_78"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RightToBuySilverProduction" xlink:label="loc_mtaff_RightToBuySilverProduction_79"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RightToDeliverSilverProductionOuncesDelivered" xlink:label="loc_mtaff_RightToDeliverSilverProductionOuncesDelivered_80"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RightToDeliverSilverProductionOuncesRemainingToBeDelivered" xlink:label="loc_mtaff_RightToDeliverSilverProductionOuncesRemainingToBeDelivered_81"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_EstimatedDeliveryOfPayableSilver" xlink:label="loc_mtaff_EstimatedDeliveryOfPayableSilver_82"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AdditionalNetSmelterReturnPercentage" xlink:label="loc_mtaff_AdditionalNetSmelterReturnPercentage_83"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExercisePriceOfWarrantsIssuedWithinUnits" xlink:label="loc_mtaff_ExercisePriceOfWarrantsIssuedWithinUnits_84"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SharePurchaseWarrantExercisePriceTerm" xlink:label="loc_mtaff_SharePurchaseWarrantExercisePriceTerm_85"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PurchasePriceForAdditionalNetSmelterRoyalty" xlink:label="loc_mtaff_PurchasePriceForAdditionalNetSmelterRoyalty_86"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfNsrInterestsAcquired" xlink:label="loc_mtaff_NumberOfNsrInterestsAcquired_87"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SharePurchaseWarrantsIssued" xlink:label="loc_mtaff_SharePurchaseWarrantsIssued_88"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NetSmelterReturnAcquisitionRange" xlink:label="loc_mtaff_NetSmelterReturnAcquisitionRange_89"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_MaximumCappingOfUnsecuredNetSmelterReturnNsr" xlink:label="loc_mtaff_MaximumCappingOfUnsecuredNetSmelterReturnNsr_90"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_MaximumCappingOfNetSmelterReturnNsr" xlink:label="loc_mtaff_MaximumCappingOfNetSmelterReturnNsr_91"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RightOfFirstRefusal" xlink:label="loc_mtaff_RightOfFirstRefusal_92"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_UpfrontPaymentMadeUponExerciseOfOption" xlink:label="loc_mtaff_UpfrontPaymentMadeUponExerciseOfOption_93"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TermOfExerciseOfOption" xlink:label="loc_mtaff_TermOfExerciseOfOption_94"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ProportionOfOwnershipInterestInSubsidiary" xlink:label="loc_ifrs-full_ProportionOfOwnershipInterestInSubsidiary_95"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SharePurchaseWarrantOutstandingExercisableAcquisition" xlink:label="loc_mtaff_SharePurchaseWarrantOutstandingExercisableAcquisition_96"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PricePerSharePurchaseWarrantOutstandingExercisableAcquisition" xlink:label="loc_mtaff_PricePerSharePurchaseWarrantOutstandingExercisableAcquisition_97"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValueOfSharePurchaseWarrantsIssued" xlink:label="loc_mtaff_ValueOfSharePurchaseWarrantsIssued_98"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_WeightedAverageFairValueOfWarrants" xlink:label="loc_mtaff_WeightedAverageFairValueOfWarrants_99"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RiskFreeInterestRateWarrantsGranted" xlink:label="loc_mtaff_RiskFreeInterestRateWarrantsGranted_100"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpectedDividendAsPercentageWarrantsGranted" xlink:label="loc_mtaff_ExpectedDividendAsPercentageWarrantsGranted_101"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpectedVolatilityWarrantsGranted" xlink:label="loc_mtaff_ExpectedVolatilityWarrantsGranted_102"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpectedLifeOfWarrantsGranted" xlink:label="loc_mtaff_ExpectedLifeOfWarrantsGranted_103"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_WarrantsForfeitureRate" xlink:label="loc_mtaff_WarrantsForfeitureRate_104"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfInferredResourceInOunces" xlink:label="loc_mtaff_NumberOfInferredResourceInOunces_105"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfBulkTonnageModel" xlink:label="loc_mtaff_NumberOfBulkTonnageModel_106"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AverageGradeOfGoldGramPerTonne" xlink:label="loc_mtaff_AverageGradeOfGoldGramPerTonne_107"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SaleOfAcquisitionToOriginalOwner" xlink:label="loc_mtaff_SaleOfAcquisitionToOriginalOwner_108"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_ifrs-full_BusinessCombinationsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_IdahoResourcesCorpAcquisitionMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_NuevaUnionAcquisitionMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_AlamosAcquisitionsMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_TowerMountainAcquisitionMember_4" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_FifteenMileStreamAcquisitionsMember_5" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_DufferinEastAcquisitionMember_6" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_CapOesteSurEastAcquisitionMember_7" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_SantaGertrudisAcquisitionsMember_8" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_ValgoldAcquisitionsMember_9" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_AkasabaWestAcquisitionMember_10" order="90" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_14" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_14" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_14" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_14" xlink:to="loc_mtaff_AgnicoEagleMinesLimitedMember_14" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_14" xlink:to="loc_mtaff_MiradoMineProjectMember_15" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_14" xlink:to="loc_mtaff_MineraTritonArgentinaMember_16" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_14" xlink:to="loc_mtaff_GarrisonProjectNsrMember_17" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_14" xlink:to="loc_mtaff_LosPlatosProjectNsrMember_18" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_14" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_ifrs-full_TypesOfInvestmentPropertyAxis_22" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_TypesOfInvestmentPropertyAxis_22" xlink:to="loc_ifrs-full_InvestmentPropertyMember_22" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_JoaquinProjectMember_22" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_ZarumaGoldMineMember_23" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_PuchuldizaProjectMember_24" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_HolyePondExtensionPropertyMember_25" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_MontclergPropertyMember_26" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_WestTimminsExtensionPropertiesMember_27" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_DesantisPropertiesMember_28" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_EitherHoylePondMineOrWestTimminsMineMember_29" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_22" xlink:to="loc_mtaff_TowerMountainProjectMember_30" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_TypesOfInvestmentPropertyAxis_22" xlink:to="loc_ifrs-full_InvestmentPropertyMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis_34" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis_34" xlink:to="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_34" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_34" xlink:to="loc_mtaff_AngloZekeNsrMember_34" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_34" xlink:to="loc_mtaff_RedHillNsrMember_35" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_34" xlink:to="loc_mtaff_BiricuNsrMember_36" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_34" xlink:to="loc_mtaff_WasamacNsrMember_37" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_34" xlink:to="loc_mtaff_ElRealitoNsrMember_38" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_34" xlink:to="loc_mtaff_LaFortunaNsrOptionMember_39" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis_34" xlink:to="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_mtaff_ConditionsAxis_43" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_ConditionsAxis_43" xlink:to="loc_mtaff_ConditionsDomain_43" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ConditionsDomain_43" xlink:to="loc_mtaff_ConditionOneMember_43" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ConditionsDomain_43" xlink:to="loc_mtaff_ConditionTwoMember_44" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ConditionsDomain_43" xlink:to="loc_mtaff_ConditionsThreeMember_45" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_ConditionsAxis_43" xlink:to="loc_mtaff_ConditionsDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_ifrs-full_CashTransferred_50" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_ifrs-full_EquityInterestsOfAcquirer_51" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests_52" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_SharePricePerShare_53" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ResultOfIndependentMineralResourceEstimationReport_54" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ProceedsFromSaleOfProject_55" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NetSmelterReturnAcquiredPercentage_56" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_PurchasePriceOfAgreement_57" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_PurchasePriceOfAgreementPayableInShares_58" order="90" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_PercentageOfCashAndCommonSharesPay_59" order="100" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_CashAndCommonSharesPaid_60" order="110" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_CashFlowsUsedForAcquisitionsOfRoyaltyAndStreamInterests_61" order="120" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_PurchasePriceOfAcquisitionPaidInCash_62" order="130" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_AcquisitionCostsForRoyaltyInterests_63" order="140" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NetSmelterReturn_64" order="150" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_ifrs-full_PaymentsForShareIssueCosts_65" order="160" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesReceivedForExchangeRatio_66" order="170" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ExemptionOnGoldProduced_67" order="180" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_BuyBackRightPercentage_68" order="190" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_HalfOfNetSmelterReturnAcquiredPercentage_69" order="200" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RightToBuyBackStreamAmount_70" order="210" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NumberOfRoyaltyInterest_71" order="220" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NumberOfSilverStreamInterests_72" order="230" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ConvertibleDebenturePayable_73" order="240" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RoyaltyInterestsAndDeferredAcquisitionCosts_74" order="250" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_OperatingCostContributionPricePerOunce_75" order="260" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_PercentageIncrementsOfExceededSilverPricePerOunce_76" order="270" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_PercentageRightToBuySilverProduction_77" order="280" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ExceedingSilverPricePerOunce_78" order="290" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RightToBuySilverProduction_79" order="300" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RightToDeliverSilverProductionOuncesDelivered_80" order="310" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RightToDeliverSilverProductionOuncesRemainingToBeDelivered_81" order="320" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_EstimatedDeliveryOfPayableSilver_82" order="330" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_AdditionalNetSmelterReturnPercentage_83" order="340" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ExercisePriceOfWarrantsIssuedWithinUnits_84" order="350" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_SharePurchaseWarrantExercisePriceTerm_85" order="360" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_PurchasePriceForAdditionalNetSmelterRoyalty_86" order="370" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NumberOfNsrInterestsAcquired_87" order="380" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_SharePurchaseWarrantsIssued_88" order="390" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NetSmelterReturnAcquisitionRange_89" order="400" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_MaximumCappingOfUnsecuredNetSmelterReturnNsr_90" order="410" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_MaximumCappingOfNetSmelterReturnNsr_91" order="420" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RightOfFirstRefusal_92" order="430" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_UpfrontPaymentMadeUponExerciseOfOption_93" order="440" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_TermOfExerciseOfOption_94" order="450" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_ifrs-full_ProportionOfOwnershipInterestInSubsidiary_95" order="460" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_SharePurchaseWarrantOutstandingExercisableAcquisition_96" order="470" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_PricePerSharePurchaseWarrantOutstandingExercisableAcquisition_97" order="480" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ValueOfSharePurchaseWarrantsIssued_98" order="490" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_WeightedAverageFairValueOfWarrants_99" order="500" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RiskFreeInterestRateWarrantsGranted_100" order="510" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ExpectedDividendAsPercentageWarrantsGranted_101" order="520" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ExpectedVolatilityWarrantsGranted_102" order="530" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ExpectedLifeOfWarrantsGranted_103" order="540" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_WarrantsForfeitureRate_104" order="550" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NumberOfInferredResourceInOunces_105" order="560" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_NumberOfBulkTonnageModel_106" order="570" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_AverageGradeOfGoldGramPerTonne_107" order="580" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_SaleOfAcquisitionToOriginalOwner_108" order="590" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/InvestmentInSilverbackNarrativeDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems" xlink:label="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesTable" xlink:label="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_SignificantInvestmentsInSubsidiariesAxis" xlink:label="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForSubsidiariesMember" xlink:label="loc_ifrs-full_EntitysTotalForSubsidiariesMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_SubsidiariesMember" xlink:label="loc_ifrs-full_SubsidiariesMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForSubsidiariesMember" xlink:label="loc_ifrs-full_EntitysTotalForSubsidiariesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ProportionOfOwnershipInterestInSubsidiary" xlink:label="loc_ifrs-full_ProportionOfOwnershipInterestInSubsidiary_6"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ConsiderationPaidReceived" xlink:label="loc_ifrs-full_ConsiderationPaidReceived_7"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInSubsidiariesTable_1" xlink:to="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForSubsidiariesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForSubsidiariesMember_1" xlink:to="loc_ifrs-full_SubsidiariesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForSubsidiariesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_ProportionOfOwnershipInterestInSubsidiary_6" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_ConsiderationPaidReceived_7" order="20" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/LoansPayableNarrativeDetails">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfLoansPayableLineItems" xlink:label="loc_mtaff_DisclosureOfLoansPayableLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfLoansPayableTable" xlink:label="loc_mtaff_DisclosureOfLoansPayableTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BusinessCombinationsAxis" xlink:label="loc_ifrs-full_BusinessCombinationsAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CoeurAcquisitionsMember" xlink:label="loc_mtaff_CoeurAcquisitionsMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TypeOfArrangementsAxis" xlink:label="loc_mtaff_TypeOfArrangementsAxis_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TypeOfArrangementsDomain" xlink:label="loc_mtaff_TypeOfArrangementsDomain_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConvertibleLoanFacilityMember" xlink:label="loc_mtaff_ConvertibleLoanFacilityMember_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoanAgreementsWithLendersMember" xlink:label="loc_mtaff_LoanAgreementsWithLendersMember_6"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TypeOfArrangementsDomain" xlink:label="loc_mtaff_TypeOfArrangementsDomain_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_RangeAxis" xlink:label="loc_ifrs-full_RangeAxis_10"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_RangesMember" xlink:label="loc_ifrs-full_RangesMember_10"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BottomOfRangeMember" xlink:label="loc_ifrs-full_BottomOfRangeMember_10"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TopOfRangeMember" xlink:label="loc_ifrs-full_TopOfRangeMember_11"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_RangesMember" xlink:label="loc_ifrs-full_RangesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CategoriesOfRelatedPartiesAxis" xlink:label="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_15"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_15"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InflectionCapitalIncMember" xlink:label="loc_mtaff_InflectionCapitalIncMember_15"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ProceedsFromCurrentBorrowings" xlink:label="loc_ifrs-full_ProceedsFromCurrentBorrowings_20"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConvertibleDebenturePayable" xlink:label="loc_mtaff_ConvertibleDebenturePayable_21"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConvertibleLoanFacility" xlink:label="loc_mtaff_ConvertibleLoanFacility_22"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InitialAdvanceOfConvertibleLoanFacility" xlink:label="loc_mtaff_InitialAdvanceOfConvertibleLoanFacility_23"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_UndrawnBorrowingFacilities" xlink:label="loc_ifrs-full_UndrawnBorrowingFacilities_24"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_MinimumTranchesOfConvertibleLoanFacility" xlink:label="loc_mtaff_MinimumTranchesOfConvertibleLoanFacility_25"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BorrowingsInterestRate" xlink:label="loc_ifrs-full_BorrowingsInterestRate_26"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AggregateOriginationDiscount" xlink:label="loc_mtaff_AggregateOriginationDiscount_27"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PercentageOfEquityOwnershipOtherCompanyNeedsToMaintainInOrderForAutomaticConversionToApply" xlink:label="loc_mtaff_PercentageOfEquityOwnershipOtherCompanyNeedsToMaintainInOrderForAutomaticConversionToApply_28"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TermOfConvertibleDebenturePayable" xlink:label="loc_mtaff_TermOfConvertibleDebenturePayable_29"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoanAgreementsForAggregateAmount" xlink:label="loc_mtaff_LoanAgreementsForAggregateAmount_30"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SecuredLoanAgreementsAggregateAmount" xlink:label="loc_mtaff_SecuredLoanAgreementsAggregateAmount_31"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SharePurchaseWarrantsIssued" xlink:label="loc_mtaff_SharePurchaseWarrantsIssued_32"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ContingentPaymentForConsiderationForLoanAgreement" xlink:label="loc_mtaff_ContingentPaymentForConsiderationForLoanAgreement_33"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_InterestReceivable" xlink:label="loc_ifrs-full_InterestReceivable_34"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoanAgreementSettled" xlink:label="loc_mtaff_LoanAgreementSettled_35"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LossOnSettlementOfLoanAgreement" xlink:label="loc_mtaff_LossOnSettlementOfLoanAgreement_36"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities" xlink:label="loc_ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities_37"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable" xlink:label="loc_mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable_38"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ParValuePerShare" xlink:label="loc_ifrs-full_ParValuePerShare_39"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments_40"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfWarrantsIssued" xlink:label="loc_mtaff_NumberOfWarrantsIssued_41"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExercisePriceOfWarrantsIssued" xlink:label="loc_mtaff_ExercisePriceOfWarrantsIssued_42"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TermOfWarrants" xlink:label="loc_mtaff_TermOfWarrants_43"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValueOfWarrantsIssued" xlink:label="loc_mtaff_ValueOfWarrantsIssued_44"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InterestRateOnStandbyFundsAvailable" xlink:label="loc_mtaff_InterestRateOnStandbyFundsAvailable_45"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PrincipalPaymentDuePeriod" xlink:label="loc_mtaff_PrincipalPaymentDuePeriod_46"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConversionPricePerShare" xlink:label="loc_mtaff_ConversionPricePerShare_47"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConvertibleLoanFacilityDrewDown" xlink:label="loc_mtaff_ConvertibleLoanFacilityDrewDown_48"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InitialAdvanceDrewDownAllocatedToLiabilityPortion" xlink:label="loc_mtaff_InitialAdvanceDrewDownAllocatedToLiabilityPortion_49"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InitialAdvanceDrewDownAllocatedToConversionFeature" xlink:label="loc_mtaff_InitialAdvanceDrewDownAllocatedToConversionFeature_50"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DeferredTaxLiabilityRelatedToTaxableTemporaryDifferenceArisingFromEquityPortion" xlink:label="loc_mtaff_DeferredTaxLiabilityRelatedToTaxableTemporaryDifferenceArisingFromEquityPortion_51"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_EffectiveInterestRateOnLiability" xlink:label="loc_mtaff_EffectiveInterestRateOnLiability_52"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpectedLifeOfLiability" xlink:label="loc_mtaff_ExpectedLifeOfLiability_53"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_FinanceCosts" xlink:label="loc_ifrs-full_FinanceCosts_54"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_DisclosureOfLoansPayableTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfLoansPayableTable_1" xlink:to="loc_ifrs-full_BusinessCombinationsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_CoeurAcquisitionsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfLoansPayableTable_1" xlink:to="loc_mtaff_TypeOfArrangementsAxis_5" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_TypeOfArrangementsAxis_5" xlink:to="loc_mtaff_TypeOfArrangementsDomain_5" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_TypeOfArrangementsDomain_5" xlink:to="loc_mtaff_ConvertibleLoanFacilityMember_5" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_TypeOfArrangementsDomain_5" xlink:to="loc_mtaff_LoanAgreementsWithLendersMember_6" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_TypeOfArrangementsAxis_5" xlink:to="loc_mtaff_TypeOfArrangementsDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfLoansPayableTable_1" xlink:to="loc_ifrs-full_RangeAxis_10" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_RangeAxis_10" xlink:to="loc_ifrs-full_RangesMember_10" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_RangesMember_10" xlink:to="loc_ifrs-full_BottomOfRangeMember_10" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_RangesMember_10" xlink:to="loc_ifrs-full_TopOfRangeMember_11" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_RangeAxis_10" xlink:to="loc_ifrs-full_RangesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfLoansPayableTable_1" xlink:to="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_15" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_15" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_15" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_15" xlink:to="loc_mtaff_InflectionCapitalIncMember_15" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_15" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_ifrs-full_ProceedsFromCurrentBorrowings_20" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_ConvertibleDebenturePayable_21" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_ConvertibleLoanFacility_22" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_InitialAdvanceOfConvertibleLoanFacility_23" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_ifrs-full_UndrawnBorrowingFacilities_24" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_MinimumTranchesOfConvertibleLoanFacility_25" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_ifrs-full_BorrowingsInterestRate_26" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_AggregateOriginationDiscount_27" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_PercentageOfEquityOwnershipOtherCompanyNeedsToMaintainInOrderForAutomaticConversionToApply_28" order="90" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_TermOfConvertibleDebenturePayable_29" order="100" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_LoanAgreementsForAggregateAmount_30" order="110" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_SecuredLoanAgreementsAggregateAmount_31" order="120" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_SharePurchaseWarrantsIssued_32" order="130" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_ContingentPaymentForConsiderationForLoanAgreement_33" order="140" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_ifrs-full_InterestReceivable_34" order="150" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_LoanAgreementSettled_35" order="160" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_LossOnSettlementOfLoanAgreement_36" order="170" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities_37" order="180" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable_38" order="190" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_ifrs-full_ParValuePerShare_39" order="200" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments_40" order="210" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_NumberOfWarrantsIssued_41" order="220" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_ExercisePriceOfWarrantsIssued_42" order="230" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_TermOfWarrants_43" order="240" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_ValueOfWarrantsIssued_44" order="250" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_InterestRateOnStandbyFundsAvailable_45" order="260" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_PrincipalPaymentDuePeriod_46" order="270" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_ConversionPricePerShare_47" order="280" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_ConvertibleLoanFacilityDrewDown_48" order="290" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_InitialAdvanceDrewDownAllocatedToLiabilityPortion_49" order="300" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_InitialAdvanceDrewDownAllocatedToConversionFeature_50" order="310" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_DeferredTaxLiabilityRelatedToTaxableTemporaryDifferenceArisingFromEquityPortion_51" order="320" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_EffectiveInterestRateOnLiability_52" order="330" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_mtaff_ExpectedLifeOfLiability_53" order="340" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfLoansPayableLineItems_0" xlink:to="loc_ifrs-full_FinanceCosts_54" order="350" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/RELATEDPARTYTRANSACTIONSANDBALANCESDetails1">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems" xlink:label="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable" xlink:label="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CategoriesOfRelatedPartiesAxis" xlink:label="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PresidentAndCeoMember" xlink:label="loc_mtaff_PresidentAndCeoMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InflectionCapitalIncMember" xlink:label="loc_mtaff_InflectionCapitalIncMember_2"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ChiefFinancialOfficerMember" xlink:label="loc_srt_ChiefFinancialOfficerMember_3"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_SignificantInvestmentsInSubsidiariesAxis" xlink:label="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForSubsidiariesMember" xlink:label="loc_ifrs-full_EntitysTotalForSubsidiariesMember_7"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_HighStreamCorpMember" xlink:label="loc_mtaff_HighStreamCorpMember_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForSubsidiariesMember" xlink:label="loc_ifrs-full_EntitysTotalForSubsidiariesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_AmountsPayableRelatedPartyTransactions" xlink:label="loc_ifrs-full_AmountsPayableRelatedPartyTransactions_12"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits" xlink:label="loc_ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits_13"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactionsInShare" xlink:label="loc_mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactionsInShare_14"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactions" xlink:label="loc_mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactions_15"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_FinderFeesPaid" xlink:label="loc_mtaff_FinderFeesPaid_16"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities" xlink:label="loc_ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities_17"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_FinancingBonusReceived" xlink:label="loc_mtaff_FinancingBonusReceived_18"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_InterestReceivable" xlink:label="loc_ifrs-full_InterestReceivable_19"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_1" xlink:to="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" xlink:to="loc_mtaff_PresidentAndCeoMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" xlink:to="loc_mtaff_InflectionCapitalIncMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" xlink:to="loc_srt_ChiefFinancialOfficerMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_1" xlink:to="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_7" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_7" xlink:to="loc_ifrs-full_EntitysTotalForSubsidiariesMember_7" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForSubsidiariesMember_7" xlink:to="loc_mtaff_HighStreamCorpMember_7" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_7" xlink:to="loc_ifrs-full_EntitysTotalForSubsidiariesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_AmountsPayableRelatedPartyTransactions_12" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits_13" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactionsInShare_14" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseThroughPerformanceBasedPaymentTransactions_15" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_mtaff_FinderFeesPaid_16" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_ProceedsFromBorrowingsClassifiedAsFinancingActivities_17" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_mtaff_FinancingBonusReceived_18" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_InterestReceivable_19" order="80" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/SupplementalDisclosureWithRespectToCashFlowsNarrativeDetails">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SupplementalDisclosureOfCashFlowLineItems" xlink:label="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SupplementalDisclosureOfCashFlowTable" xlink:label="loc_mtaff_SupplementalDisclosureOfCashFlowTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BusinessCombinationsAxis" xlink:label="loc_ifrs-full_BusinessCombinationsAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IdahoResourcesCorpAcquisitionMember" xlink:label="loc_mtaff_IdahoResourcesCorpAcquisitionMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AlamosAcquisitionsMember" xlink:label="loc_mtaff_AlamosAcquisitionsMember_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NuevaUnionAcquisitionMember" xlink:label="loc_mtaff_NuevaUnionAcquisitionMember_3"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TowerMountainAcquisitionMember" xlink:label="loc_mtaff_TowerMountainAcquisitionMember_4"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SantaGertrudisAcquisitonsMember" xlink:label="loc_mtaff_SantaGertrudisAcquisitonsMember_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValgoldAcquisitionsMember" xlink:label="loc_mtaff_ValgoldAcquisitionsMember_6"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_FifteenMileStreamAcquisitionsMember" xlink:label="loc_mtaff_FifteenMileStreamAcquisitionsMember_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TypesOfInvestmentPropertyAxis" xlink:label="loc_ifrs-full_TypesOfInvestmentPropertyAxis_11"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_InvestmentPropertyMember" xlink:label="loc_ifrs-full_InvestmentPropertyMember_11"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TowerMountainProjectMember" xlink:label="loc_mtaff_TowerMountainProjectMember_11"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_InvestmentPropertyMember" xlink:label="loc_ifrs-full_InvestmentPropertyMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests" xlink:label="loc_mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests_16"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfSharePurchaseWarrantsIssuedForAcquisitionsOfRoyaltyInterests" xlink:label="loc_mtaff_NumberOfSharePurchaseWarrantsIssuedForAcquisitionsOfRoyaltyInterests_17"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AggregateValueOfAcquisitionsOfRoyaltyInterests" xlink:label="loc_mtaff_AggregateValueOfAcquisitionsOfRoyaltyInterests_18"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TradeAndOtherPayablesRecognisedAsOfAcquisitionDate" xlink:label="loc_ifrs-full_TradeAndOtherPayablesRecognisedAsOfAcquisitionDate_19"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ProceedsFromSaleOfProject" xlink:label="loc_mtaff_ProceedsFromSaleOfProject_20"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NetSmelterReturnAcquiredPercentage" xlink:label="loc_mtaff_NetSmelterReturnAcquiredPercentage_21"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesIssuedForVestingOfRestrictedStockUnits" xlink:label="loc_mtaff_NumberOfCommonSharesIssuedForVestingOfRestrictedStockUnits_22"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValueOfSharesIssuedForVestingOfRestrictedStockUnits" xlink:label="loc_mtaff_ValueOfSharesIssuedForVestingOfRestrictedStockUnits_23"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ReallocationFromReservesForStockOptionsExercised" xlink:label="loc_mtaff_ReallocationFromReservesForStockOptionsExercised_24"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NumberOfShareOptionsExercisedInSharebasedPaymentArrangement" xlink:label="loc_ifrs-full_NumberOfShareOptionsExercisedInSharebasedPaymentArrangement_25"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ReallocationFromReservesForSharePurchaseWarrantsExercised" xlink:label="loc_mtaff_ReallocationFromReservesForSharePurchaseWarrantsExercised_26"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfSharePurchaseWarrantsExercised" xlink:label="loc_mtaff_NumberOfSharePurchaseWarrantsExercised_27"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AggregateValueOfCommonSharesAndConvertibleDebentureForNetAssetsAcquired" xlink:label="loc_mtaff_AggregateValueOfCommonSharesAndConvertibleDebentureForNetAssetsAcquired_28"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfSharePurchaseWarrantsIssuedOnSettlementOfLoansPayable" xlink:label="loc_mtaff_NumberOfSharePurchaseWarrantsIssuedOnSettlementOfLoansPayable_29"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseLoansPayableThroughIssuedOfWarrants" xlink:label="loc_mtaff_IncreaseDecreaseLoansPayableThroughIssuedOfWarrants_30"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments" xlink:label="loc_ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments_31"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable" xlink:label="loc_mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable_32"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfUnderwritersWarrantsIssued" xlink:label="loc_mtaff_NumberOfUnderwritersWarrantsIssued_33"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValueOfUnderwritersWarrantsIssued" xlink:label="loc_mtaff_ValueOfUnderwritersWarrantsIssued_34"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesIssuedForNetAssetsAcquired" xlink:label="loc_mtaff_NumberOfCommonSharesIssuedForNetAssetsAcquired_35"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ReallocationOfDeferredAcquisitionCostsToRoyaltyAndStreamInterestsOnClosingOfAcquisition" xlink:label="loc_mtaff_ReallocationOfDeferredAcquisitionCostsToRoyaltyAndStreamInterestsOnClosingOfAcquisition_36"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesAcquisition" xlink:label="loc_mtaff_NumberOfCommonSharesAcquisition_37"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValueOfCommonSharesAcquisition" xlink:label="loc_mtaff_ValueOfCommonSharesAcquisition_38"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_SupplementalDisclosureOfCashFlowTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowTable_1" xlink:to="loc_ifrs-full_BusinessCombinationsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_IdahoResourcesCorpAcquisitionMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_AlamosAcquisitionsMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_NuevaUnionAcquisitionMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_TowerMountainAcquisitionMember_4" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_SantaGertrudisAcquisitonsMember_5" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_ValgoldAcquisitionsMember_6" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_FifteenMileStreamAcquisitionsMember_7" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowTable_1" xlink:to="loc_ifrs-full_TypesOfInvestmentPropertyAxis_11" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_TypesOfInvestmentPropertyAxis_11" xlink:to="loc_ifrs-full_InvestmentPropertyMember_11" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_InvestmentPropertyMember_11" xlink:to="loc_mtaff_TowerMountainProjectMember_11" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_TypesOfInvestmentPropertyAxis_11" xlink:to="loc_ifrs-full_InvestmentPropertyMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests_16" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NumberOfSharePurchaseWarrantsIssuedForAcquisitionsOfRoyaltyInterests_17" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_AggregateValueOfAcquisitionsOfRoyaltyInterests_18" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_ifrs-full_TradeAndOtherPayablesRecognisedAsOfAcquisitionDate_19" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_ProceedsFromSaleOfProject_20" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NetSmelterReturnAcquiredPercentage_21" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesIssuedForVestingOfRestrictedStockUnits_22" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_ValueOfSharesIssuedForVestingOfRestrictedStockUnits_23" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_ReallocationFromReservesForStockOptionsExercised_24" order="90" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_ifrs-full_NumberOfShareOptionsExercisedInSharebasedPaymentArrangement_25" order="100" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_ReallocationFromReservesForSharePurchaseWarrantsExercised_26" order="110" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NumberOfSharePurchaseWarrantsExercised_27" order="120" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_AggregateValueOfCommonSharesAndConvertibleDebentureForNetAssetsAcquired_28" order="130" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NumberOfSharePurchaseWarrantsIssuedOnSettlementOfLoansPayable_29" order="140" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseLoansPayableThroughIssuedOfWarrants_30" order="150" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_ifrs-full_IncreaseDecreaseThroughConversionOfConvertibleInstruments_31" order="160" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable_32" order="170" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NumberOfUnderwritersWarrantsIssued_33" order="180" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_ValueOfUnderwritersWarrantsIssued_34" order="190" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesIssuedForNetAssetsAcquired_35" order="200" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_ReallocationOfDeferredAcquisitionCostsToRoyaltyAndStreamInterestsOnClosingOfAcquisition_36" order="210" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesAcquisition_37" order="220" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SupplementalDisclosureOfCashFlowLineItems_0" xlink:to="loc_mtaff_ValueOfCommonSharesAcquisition_38" order="230" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/FinancialInstrumentsNarrativeDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfFinancialInstrumentsLineItems" xlink:label="loc_ifrs-full_DisclosureOfFinancialInstrumentsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfFinancialInstrumentsTable" xlink:label="loc_ifrs-full_DisclosureOfFinancialInstrumentsTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TypesOfRisksAxis" xlink:label="loc_ifrs-full_TypesOfRisksAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TypesOfRisksMember" xlink:label="loc_ifrs-full_TypesOfRisksMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CurrencyRiskMember" xlink:label="loc_ifrs-full_CurrencyRiskMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TypesOfRisksMember" xlink:label="loc_ifrs-full_TypesOfRisksMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SensitivityAnalysisVariancePrice" xlink:label="loc_mtaff_SensitivityAnalysisVariancePrice_6"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ValueAtRisk" xlink:label="loc_ifrs-full_ValueAtRisk_7"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfFinancialInstrumentsLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfFinancialInstrumentsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfFinancialInstrumentsTable_1" xlink:to="loc_ifrs-full_TypesOfRisksAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_TypesOfRisksAxis_1" xlink:to="loc_ifrs-full_TypesOfRisksMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TypesOfRisksMember_1" xlink:to="loc_ifrs-full_CurrencyRiskMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_TypesOfRisksAxis_1" xlink:to="loc_ifrs-full_TypesOfRisksMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFinancialInstrumentsLineItems_0" xlink:to="loc_mtaff_SensitivityAnalysisVariancePrice_6" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfFinancialInstrumentsLineItems_0" xlink:to="loc_ifrs-full_ValueAtRisk_7" order="20" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/EventsAfterReportingDateNarrativeDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems" xlink:label="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable" xlink:label="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NonadjustingEventsAfterReportingPeriodAxis" xlink:label="loc_ifrs-full_NonadjustingEventsAfterReportingPeriodAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NonadjustingEventsMember" xlink:label="loc_ifrs-full_NonadjustingEventsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_EventsAfterReportingPeriodMember" xlink:label="loc_mtaff_EventsAfterReportingPeriodMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NonadjustingEventsMember" xlink:label="loc_ifrs-full_NonadjustingEventsMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TypeOfArrangementsAxis" xlink:label="loc_mtaff_TypeOfArrangementsAxis_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TypeOfArrangementsDomain" xlink:label="loc_mtaff_TypeOfArrangementsDomain_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AgreementWithNuEnergyGasLimitedMember" xlink:label="loc_mtaff_AgreementWithNuEnergyGasLimitedMember_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConvertibleLoanFacilityMember" xlink:label="loc_mtaff_ConvertibleLoanFacilityMember_6"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TypeOfArrangementsDomain" xlink:label="loc_mtaff_TypeOfArrangementsDomain_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LegalEntitiesAxis" xlink:label="loc_mtaff_LegalEntitiesAxis_10"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LegalEntitiesDomain" xlink:label="loc_mtaff_LegalEntitiesDomain_10"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CoeurMiningIncMember" xlink:label="loc_mtaff_CoeurMiningIncMember_10"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_KirklandLakeGoldLtdMember" xlink:label="loc_mtaff_KirklandLakeGoldLtdMember_11"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_BeedieCapitalMember" xlink:label="loc_mtaff_BeedieCapitalMember_12"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LegalEntitiesDomain" xlink:label="loc_mtaff_LegalEntitiesDomain_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SaleOfStocksAxis" xlink:label="loc_mtaff_SaleOfStocksAxis_16"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SaleOfStocksDomain" xlink:label="loc_mtaff_SaleOfStocksDomain_16"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SecondaryOfferingMember" xlink:label="loc_mtaff_SecondaryOfferingMember_16"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SaleOfStocksDomain" xlink:label="loc_mtaff_SaleOfStocksDomain_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BusinessCombinationsAxis" xlink:label="loc_ifrs-full_BusinessCombinationsAxis_20"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_20"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_WharfAcquisitionMember" xlink:label="loc_mtaff_WharfAcquisitionMember_20"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_PercentageOfNetSmelterReturnRoyaltyAcquired" xlink:label="loc_mtaff_PercentageOfNetSmelterReturnRoyaltyAcquired_25"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CashTransferred" xlink:label="loc_ifrs-full_CashTransferred_26"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests" xlink:label="loc_mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests_27"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfSharesInPublicOfferingPreviouslyHeld" xlink:label="loc_mtaff_NumberOfSharesInPublicOfferingPreviouslyHeld_28"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_EquityIssuancePricePerShare" xlink:label="loc_mtaff_EquityIssuancePricePerShare_29"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ProceedsFromIssuingShares" xlink:label="loc_ifrs-full_ProceedsFromIssuingShares_30"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CashFlowsUsedForAcquisitionsOfRoyaltyAndStreamInterests" xlink:label="loc_mtaff_CashFlowsUsedForAcquisitionsOfRoyaltyAndStreamInterests_31"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_PurchaseOfMiningAssets" xlink:label="loc_ifrs-full_PurchaseOfMiningAssets_32"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConversionOfLoanFacilityConvertedAmount" xlink:label="loc_mtaff_ConversionOfLoanFacilityConvertedAmount_33"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InitialAdvanceOfConvertibleLoanFacility" xlink:label="loc_mtaff_InitialAdvanceOfConvertibleLoanFacility_34"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConvertibleLoanFacilityRemainingDrewDownFromOriginalLoanFacility" xlink:label="loc_mtaff_ConvertibleLoanFacilityRemainingDrewDownFromOriginalLoanFacility_35"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AdditionalConvertibleLoanFacilityToFundFutureAcquisitions" xlink:label="loc_mtaff_AdditionalConvertibleLoanFacilityToFundFutureAcquisitions_36"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ConversionPricePerShare" xlink:label="loc_mtaff_ConversionPricePerShare_37"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable" xlink:label="loc_mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable_38"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RevisedConversionPrice" xlink:label="loc_mtaff_RevisedConversionPrice_39"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable_1" xlink:to="loc_ifrs-full_NonadjustingEventsAfterReportingPeriodAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_NonadjustingEventsAfterReportingPeriodAxis_1" xlink:to="loc_ifrs-full_NonadjustingEventsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_NonadjustingEventsMember_1" xlink:to="loc_mtaff_EventsAfterReportingPeriodMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_NonadjustingEventsAfterReportingPeriodAxis_1" xlink:to="loc_ifrs-full_NonadjustingEventsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable_1" xlink:to="loc_mtaff_TypeOfArrangementsAxis_5" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_TypeOfArrangementsAxis_5" xlink:to="loc_mtaff_TypeOfArrangementsDomain_5" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_TypeOfArrangementsDomain_5" xlink:to="loc_mtaff_AgreementWithNuEnergyGasLimitedMember_5" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_TypeOfArrangementsDomain_5" xlink:to="loc_mtaff_ConvertibleLoanFacilityMember_6" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_TypeOfArrangementsAxis_5" xlink:to="loc_mtaff_TypeOfArrangementsDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable_1" xlink:to="loc_mtaff_LegalEntitiesAxis_10" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_LegalEntitiesAxis_10" xlink:to="loc_mtaff_LegalEntitiesDomain_10" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LegalEntitiesDomain_10" xlink:to="loc_mtaff_CoeurMiningIncMember_10" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LegalEntitiesDomain_10" xlink:to="loc_mtaff_KirklandLakeGoldLtdMember_11" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LegalEntitiesDomain_10" xlink:to="loc_mtaff_BeedieCapitalMember_12" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_LegalEntitiesAxis_10" xlink:to="loc_mtaff_LegalEntitiesDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable_1" xlink:to="loc_mtaff_SaleOfStocksAxis_16" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_SaleOfStocksAxis_16" xlink:to="loc_mtaff_SaleOfStocksDomain_16" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_SaleOfStocksDomain_16" xlink:to="loc_mtaff_SecondaryOfferingMember_16" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_SaleOfStocksAxis_16" xlink:to="loc_mtaff_SaleOfStocksDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodTable_1" xlink:to="loc_ifrs-full_BusinessCombinationsAxis_20" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_20" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_20" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_20" xlink:to="loc_mtaff_WharfAcquisitionMember_20" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_20" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_PercentageOfNetSmelterReturnRoyaltyAcquired_25" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_ifrs-full_CashTransferred_26" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_NumberOfCommonSharesIssuedForAcquisitionsOfRoyaltyInterests_27" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_NumberOfSharesInPublicOfferingPreviouslyHeld_28" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_EquityIssuancePricePerShare_29" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_ifrs-full_ProceedsFromIssuingShares_30" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_CashFlowsUsedForAcquisitionsOfRoyaltyAndStreamInterests_31" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_ifrs-full_PurchaseOfMiningAssets_32" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_ConversionOfLoanFacilityConvertedAmount_33" order="90" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_InitialAdvanceOfConvertibleLoanFacility_34" order="100" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_ConvertibleLoanFacilityRemainingDrewDownFromOriginalLoanFacility_35" order="110" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_AdditionalConvertibleLoanFacilityToFundFutureAcquisitions_36" order="120" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_ConversionPricePerShare_37" order="130" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_IncreaseDecreaseSharesThroughConversionOnLoanPayable_38" order="140" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems_0" xlink:to="loc_mtaff_RevisedConversionPrice_39" order="150" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfDetailedInformationAboutRoyaltyInterestsAndDeferredAcquisitionCostsDetails">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems" xlink:label="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable" xlink:label="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis" xlink:label="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain" xlink:label="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CoeurStreamAndRoyaltyInterestsMember" xlink:label="loc_mtaff_CoeurStreamAndRoyaltyInterestsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AlamosRoyaltyInterestsMember" xlink:label="loc_mtaff_AlamosRoyaltyInterestsMember_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_OtherRoyaltyInterestsMember" xlink:label="loc_mtaff_OtherRoyaltyInterestsMember_3"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain" xlink:label="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BusinessCombinationsAxis" xlink:label="loc_ifrs-full_BusinessCombinationsAxis_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AlamosAcquisitionsMember" xlink:label="loc_mtaff_AlamosAcquisitionsMember_7"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValgoldAcquisitionsMember" xlink:label="loc_mtaff_ValgoldAcquisitionsMember_8"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_SantaGertrudisAcquisitonsMember" xlink:label="loc_mtaff_SantaGertrudisAcquisitonsMember_9"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CoseAcquisitionsMember" xlink:label="loc_mtaff_CoseAcquisitionsMember_10"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_FifteenMileStreamAcquisitionsMember" xlink:label="loc_mtaff_FifteenMileStreamAcquisitionsMember_11"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NuevaUnionAcquisitionMember" xlink:label="loc_mtaff_NuevaUnionAcquisitionMember_12"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IdahoResourcesCorpAcquisitionMember" xlink:label="loc_mtaff_IdahoResourcesCorpAcquisitionMember_13"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RoyaltyAndStreamInterests" xlink:label="loc_mtaff_RoyaltyAndStreamInterests_18"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RoyaltyInterestsAndDeferredAcquisitionCosts" xlink:label="loc_mtaff_RoyaltyInterestsAndDeferredAcquisitionCosts_19"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_OtherAcquisitionCostsOfRoyaltyAndStreamInterests" xlink:label="loc_mtaff_OtherAcquisitionCostsOfRoyaltyAndStreamInterests_20"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_OtherAdditionsRoyaltyAndStreamInterests" xlink:label="loc_mtaff_OtherAdditionsRoyaltyAndStreamInterests_21"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DepletionOfRoyaltyAndStreamInterests" xlink:label="loc_mtaff_DepletionOfRoyaltyAndStreamInterests_22"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RecoveriesOfRoyaltyAndStreamInterests" xlink:label="loc_mtaff_RecoveriesOfRoyaltyAndStreamInterests_23"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ReclassificationOfRoyaltyAndStreamInterests" xlink:label="loc_mtaff_ReclassificationOfRoyaltyAndStreamInterests_24"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationNetOfTax" xlink:label="loc_ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationNetOfTax_25"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_HistoricalCostsRoyaltyAndStreamInterests" xlink:label="loc_mtaff_HistoricalCostsRoyaltyAndStreamInterests_26"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AccumulatedDepletionRoyaltyAndStreamInterests" xlink:label="loc_mtaff_AccumulatedDepletionRoyaltyAndStreamInterests_27"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis_1" xlink:to="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_1" xlink:to="loc_mtaff_CoeurStreamAndRoyaltyInterestsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_1" xlink:to="loc_mtaff_AlamosRoyaltyInterestsMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_1" xlink:to="loc_mtaff_OtherRoyaltyInterestsMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsAxis_1" xlink:to="loc_mtaff_CategoriesOfRoyaltyStreamsAndInterestsDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_ifrs-full_BusinessCombinationsAxis_7" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_7" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7" xlink:to="loc_mtaff_AlamosAcquisitionsMember_7" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7" xlink:to="loc_mtaff_ValgoldAcquisitionsMember_8" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7" xlink:to="loc_mtaff_SantaGertrudisAcquisitonsMember_9" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7" xlink:to="loc_mtaff_CoseAcquisitionsMember_10" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7" xlink:to="loc_mtaff_FifteenMileStreamAcquisitionsMember_11" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7" xlink:to="loc_mtaff_NuevaUnionAcquisitionMember_12" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_7" xlink:to="loc_mtaff_IdahoResourcesCorpAcquisitionMember_13" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_7" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RoyaltyAndStreamInterests_18" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RoyaltyInterestsAndDeferredAcquisitionCosts_19" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_OtherAcquisitionCostsOfRoyaltyAndStreamInterests_20" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_OtherAdditionsRoyaltyAndStreamInterests_21" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_DepletionOfRoyaltyAndStreamInterests_22" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_RecoveriesOfRoyaltyAndStreamInterests_23" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_ReclassificationOfRoyaltyAndStreamInterests_24" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_ifrs-full_GainsLossesOnExchangeDifferencesOnTranslationNetOfTax_25" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_HistoricalCostsRoyaltyAndStreamInterests_26" order="90" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_AccumulatedDepletionRoyaltyAndStreamInterests_27" order="100" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfDetailedInformationAboutPurchasePriceAllocationForAcquisitionDetails">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems" xlink:label="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable" xlink:label="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_BusinessCombinationsAxis" xlink:label="loc_ifrs-full_BusinessCombinationsAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_IdahoResourcesCorpAcquisitionMember" xlink:label="loc_mtaff_IdahoResourcesCorpAcquisitionMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ValgoldAcquisitionsMember" xlink:label="loc_mtaff_ValgoldAcquisitionsMember_2"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForBusinessCombinationsMember" xlink:label="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract" xlink:label="loc_ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CashTransferred" xlink:label="loc_ifrs-full_CashTransferred_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EquityInterestsOfAcquirer" xlink:label="loc_ifrs-full_EquityInterestsOfAcquirer_8"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ReserveForSharePurchaseWarrants" xlink:label="loc_mtaff_ReserveForSharePurchaseWarrants_9"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_LiabilitiesIncurred" xlink:label="loc_ifrs-full_LiabilitiesIncurred_10"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_AcquisitionrelatedCostsRecognisedAsExpenseForTransactionRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination" xlink:label="loc_ifrs-full_AcquisitionrelatedCostsRecognisedAsExpenseForTransactionRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination_11"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ConsiderationPaidReceived" xlink:label="loc_ifrs-full_ConsiderationPaidReceived_12"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract" xlink:label="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CashAndCashEquivalentsRecognisedAsOfAcquisitionDate" xlink:label="loc_ifrs-full_CashAndCashEquivalentsRecognisedAsOfAcquisitionDate_14"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_FinancialAssetsRecognisedAsOfAcquisitionDate" xlink:label="loc_ifrs-full_FinancialAssetsRecognisedAsOfAcquisitionDate_15"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TradeAndOtherReceivables" xlink:label="loc_ifrs-full_TradeAndOtherReceivables_16"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CurrentTradeReceivables" xlink:label="loc_ifrs-full_CurrentTradeReceivables_17"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IdentifiableIntangibleAssetsRecognisedAsOfAcquisitionDate" xlink:label="loc_ifrs-full_IdentifiableIntangibleAssetsRecognisedAsOfAcquisitionDate_18"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_EndeavorStreamInterestAsOfAcquisitionDate" xlink:label="loc_mtaff_EndeavorStreamInterestAsOfAcquisitionDate_19"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TradeAndOtherPayablesRecognisedAsOfAcquisitionDate" xlink:label="loc_ifrs-full_TradeAndOtherPayablesRecognisedAsOfAcquisitionDate_20"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_IdentifiableAssetsAcquiredLiabilitiesAssumed" xlink:label="loc_ifrs-full_IdentifiableAssetsAcquiredLiabilitiesAssumed_21"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsTable_1" xlink:to="loc_ifrs-full_BusinessCombinationsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_IdahoResourcesCorpAcquisitionMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_1" xlink:to="loc_mtaff_ValgoldAcquisitionsMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_BusinessCombinationsAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForBusinessCombinationsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract_7" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract_7" xlink:to="loc_ifrs-full_CashTransferred_7" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract_7" xlink:to="loc_ifrs-full_EquityInterestsOfAcquirer_8" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract_7" xlink:to="loc_mtaff_ReserveForSharePurchaseWarrants_9" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract_7" xlink:to="loc_ifrs-full_LiabilitiesIncurred_10" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract_7" xlink:to="loc_ifrs-full_AcquisitionrelatedCostsRecognisedAsExpenseForTransactionRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination_11" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferredAbstract_7" xlink:to="loc_ifrs-full_ConsiderationPaidReceived_12" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DisclosureOfRoyaltyInterestsAndDeferredAcquisitionCostsLineItems_0" xlink:to="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" xlink:to="loc_ifrs-full_CashAndCashEquivalentsRecognisedAsOfAcquisitionDate_14" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" xlink:to="loc_ifrs-full_FinancialAssetsRecognisedAsOfAcquisitionDate_15" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" xlink:to="loc_ifrs-full_TradeAndOtherReceivables_16" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" xlink:to="loc_ifrs-full_CurrentTradeReceivables_17" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" xlink:to="loc_ifrs-full_IdentifiableIntangibleAssetsRecognisedAsOfAcquisitionDate_18" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" xlink:to="loc_mtaff_EndeavorStreamInterestAsOfAcquisitionDate_19" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" xlink:to="loc_ifrs-full_TradeAndOtherPayablesRecognisedAsOfAcquisitionDate_20" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AmountsRecognisedAsOfAcquisitionDateForEachMajorClassOfAssetsAcquiredAndLiabilitiesAssumedAbstract_14" xlink:to="loc_ifrs-full_IdentifiableAssetsAcquiredLiabilitiesAssumed_21" order="70" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfTransactionsRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombinationDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems" xlink:label="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesTable" xlink:label="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CategoriesOfRelatedPartiesAxis" xlink:label="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_SubsidiariesMember" xlink:label="loc_ifrs-full_SubsidiariesMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_InvestmentAccountedForUsingEquityMethod" xlink:label="loc_ifrs-full_InvestmentAccountedForUsingEquityMethod_6"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod" xlink:label="loc_ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DividendsReceived" xlink:label="loc_ifrs-full_DividendsReceived_8"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesTable_1" xlink:to="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" xlink:to="loc_ifrs-full_SubsidiariesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_InvestmentAccountedForUsingEquityMethod_6" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_ShareOfProfitLossOfAssociatesAccountedForUsingEquityMethod_7" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_DividendsReceived_8" order="30" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfSubsidiaryDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems" xlink:label="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesTable" xlink:label="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CategoriesOfRelatedPartiesAxis" xlink:label="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_SubsidiariesMember" xlink:label="loc_ifrs-full_SubsidiariesMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CurrentAssets" xlink:label="loc_ifrs-full_CurrentAssets_6"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NoncurrentAssets" xlink:label="loc_ifrs-full_NoncurrentAssets_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_Assets" xlink:label="loc_ifrs-full_Assets_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_Liabilities" xlink:label="loc_ifrs-full_Liabilities_9"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RevenueFromStreamInterest" xlink:label="loc_mtaff_RevenueFromStreamInterest_10"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DepletionOnStreamInterest" xlink:label="loc_mtaff_DepletionOnStreamInterest_11"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ComprehensiveIncome" xlink:label="loc_ifrs-full_ComprehensiveIncome_12"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesTable_1" xlink:to="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" xlink:to="loc_ifrs-full_SubsidiariesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_CurrentAssets_6" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_NoncurrentAssets_7" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_Assets_8" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_Liabilities_9" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_mtaff_RevenueFromStreamInterest_10" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_mtaff_DepletionOnStreamInterest_11" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfSignificantInvestmentsInAssociatesLineItems_0" xlink:to="loc_ifrs-full_ComprehensiveIncome_12" order="70" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfDetailedInformationAboutLoansPayableDetails">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoanPayableLineItems" xlink:label="loc_mtaff_LoanPayableLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoanPayableTable" xlink:label="loc_mtaff_LoanPayableTable_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoanPayableAxis" xlink:label="loc_mtaff_LoanPayableAxis_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoanPayableDomain" xlink:label="loc_mtaff_LoanPayableDomain_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_BeedieMember" xlink:label="loc_mtaff_BeedieMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CoeurDebentureMember" xlink:label="loc_mtaff_CoeurDebentureMember_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_OtherLoanPayableMember" xlink:label="loc_mtaff_OtherLoanPayableMember_3"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoanPayableDomain" xlink:label="loc_mtaff_LoanPayableDomain_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_Borrowings" xlink:label="loc_ifrs-full_Borrowings_8"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AdditionsToLoanPayable" xlink:label="loc_mtaff_AdditionsToLoanPayable_9"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InitialAdvanceDrewDownAllocatedToConversionFeature" xlink:label="loc_mtaff_InitialAdvanceDrewDownAllocatedToConversionFeature_10"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_InducementsToLoanPayable" xlink:label="loc_mtaff_InducementsToLoanPayable_11"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_InterestExpense" xlink:label="loc_ifrs-full_InterestExpense_12"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_RepaymentsOfCurrentBorrowings" xlink:label="loc_ifrs-full_RepaymentsOfCurrentBorrowings_13"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_LoansSettlement" xlink:label="loc_mtaff_LoansSettlement_14"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CurrencyTranslationAdjustmentsRelatedToBorrowings" xlink:label="loc_mtaff_CurrencyTranslationAdjustmentsRelatedToBorrowings_15"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ShorttermBorrowings" xlink:label="loc_ifrs-full_ShorttermBorrowings_16"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_LongtermBorrowings" xlink:label="loc_ifrs-full_LongtermBorrowings_17"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_mtaff_LoanPayableTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_LoanPayableTable_1" xlink:to="loc_mtaff_LoanPayableAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_LoanPayableAxis_1" xlink:to="loc_mtaff_LoanPayableDomain_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableDomain_1" xlink:to="loc_mtaff_BeedieMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableDomain_1" xlink:to="loc_mtaff_CoeurDebentureMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableDomain_1" xlink:to="loc_mtaff_OtherLoanPayableMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_LoanPayableAxis_1" xlink:to="loc_mtaff_LoanPayableDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_ifrs-full_Borrowings_8" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_mtaff_AdditionsToLoanPayable_9" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_mtaff_InitialAdvanceDrewDownAllocatedToConversionFeature_10" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_mtaff_InducementsToLoanPayable_11" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_ifrs-full_InterestExpense_12" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_ifrs-full_RepaymentsOfCurrentBorrowings_13" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_mtaff_LoansSettlement_14" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_mtaff_CurrencyTranslationAdjustmentsRelatedToBorrowings_15" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_ifrs-full_ShorttermBorrowings_16" order="90" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_LoanPayableLineItems_0" xlink:to="loc_ifrs-full_LongtermBorrowings_17" order="100" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfDeferredIncomeTaxAssetLiabilityDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems" xlink:label="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable" xlink:label="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis" xlink:label="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember" xlink:label="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_MineralExpendituresAndCapitalAssetsMember" xlink:label="loc_mtaff_MineralExpendituresAndCapitalAssetsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ShareIssueCostsMember" xlink:label="loc_mtaff_ShareIssueCostsMember_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NonCapitalLossesAndOtherMember" xlink:label="loc_mtaff_NonCapitalLossesAndOtherMember_3"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember" xlink:label="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DeferredTaxAssetsAndLiabilitiesAbstract" xlink:label="loc_ifrs-full_DeferredTaxAssetsAndLiabilitiesAbstract_8"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DeferredTaxAssetsAbstract" xlink:label="loc_mtaff_DeferredTaxAssetsAbstract_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DeferredTaxAssets" xlink:label="loc_ifrs-full_DeferredTaxAssets_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised" xlink:label="loc_ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised_9"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DeferredTaxLiabilities" xlink:label="loc_ifrs-full_DeferredTaxLiabilities_10"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DeferredTaxLiabilityAsset" xlink:label="loc_ifrs-full_DeferredTaxLiabilityAsset_11"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable_1" xlink:to="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis_1" xlink:to="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1" xlink:to="loc_mtaff_MineralExpendituresAndCapitalAssetsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1" xlink:to="loc_mtaff_ShareIssueCostsMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1" xlink:to="loc_mtaff_NonCapitalLossesAndOtherMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis_1" xlink:to="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems_0" xlink:to="loc_ifrs-full_DeferredTaxAssetsAndLiabilitiesAbstract_8" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DeferredTaxAssetsAndLiabilitiesAbstract_8" xlink:to="loc_mtaff_DeferredTaxAssetsAbstract_8" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DeferredTaxAssetsAbstract_8" xlink:to="loc_ifrs-full_DeferredTaxAssets_8" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DeferredTaxAssetsAbstract_8" xlink:to="loc_ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised_9" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DeferredTaxAssetsAbstract_8" xlink:to="loc_ifrs-full_DeferredTaxLiabilities_10" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DeferredTaxAssetsAbstract_8" xlink:to="loc_ifrs-full_DeferredTaxLiabilityAsset_11" order="30" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfRangeOfExercisePricesOfOutstandingShareOptionsDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems" xlink:label="loc_ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsTable" xlink:label="loc_ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsTable_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateAxis" xlink:label="loc_mtaff_ExpiryDateAxis_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateDomain" xlink:label="loc_mtaff_ExpiryDateDomain_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateJul152021Member" xlink:label="loc_mtaff_ExpiryDateJul152021Member_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateNov152021Member" xlink:label="loc_mtaff_ExpiryDateNov152021Member_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateNov302021Member" xlink:label="loc_mtaff_ExpiryDateNov302021Member_3"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateMar062022Member" xlink:label="loc_mtaff_ExpiryDateMar062022Member_4"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateJul312022Member" xlink:label="loc_mtaff_ExpiryDateJul312022Member_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateMar012023Member" xlink:label="loc_mtaff_ExpiryDateMar012023Member_6"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateSep182023Member" xlink:label="loc_mtaff_ExpiryDateSep182023Member_7"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateJan042024Member" xlink:label="loc_mtaff_ExpiryDateJan042024Member_8"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateJan152025Member" xlink:label="loc_mtaff_ExpiryDateJan152025Member_9"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateDomain" xlink:label="loc_mtaff_ExpiryDateDomain_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ExercisePriceOfOutstandingShareOptions2019" xlink:label="loc_ifrs-full_ExercisePriceOfOutstandingShareOptions2019_14"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NumberOfOutstandingShareOptions" xlink:label="loc_ifrs-full_NumberOfOutstandingShareOptions_15"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NumberOfShareOptionsExercisableInSharebasedPaymentArrangement" xlink:label="loc_ifrs-full_NumberOfShareOptionsExercisableInSharebasedPaymentArrangement_16"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsTable_1" xlink:to="loc_mtaff_ExpiryDateAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_ExpiryDateAxis_1" xlink:to="loc_mtaff_ExpiryDateDomain_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateJul152021Member_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateNov152021Member_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateNov302021Member_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateMar062022Member_4" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateJul312022Member_5" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateMar012023Member_6" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateSep182023Member_7" order="60" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateJan042024Member_8" order="70" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateJan152025Member_9" order="80" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_ExpiryDateAxis_1" xlink:to="loc_mtaff_ExpiryDateDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems_0" xlink:to="loc_ifrs-full_ExercisePriceOfOutstandingShareOptions2019_14" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems_0" xlink:to="loc_ifrs-full_NumberOfOutstandingShareOptions_15" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems_0" xlink:to="loc_ifrs-full_NumberOfShareOptionsExercisableInSharebasedPaymentArrangement_16" order="30" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfRangeOfExercisePricesOfOutstandingWarrantsDetails">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ScheduleOfWarrantLineItems" xlink:label="loc_mtaff_ScheduleOfWarrantLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ScheduleOfWarrantTable" xlink:label="loc_mtaff_ScheduleOfWarrantTable_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateAxis" xlink:label="loc_mtaff_ExpiryDateAxis_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateDomain" xlink:label="loc_mtaff_ExpiryDateDomain_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateNovember082020Member" xlink:label="loc_mtaff_ExpiryDateNovember082020Member_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateDecember212020Member" xlink:label="loc_mtaff_ExpiryDateDecember212020Member_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateDecember212020OneMember" xlink:label="loc_mtaff_ExpiryDateDecember212020OneMember_3"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateJanuary042021Member" xlink:label="loc_mtaff_ExpiryDateJanuary042021Member_4"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateJanuary042021OneMember" xlink:label="loc_mtaff_ExpiryDateJanuary042021OneMember_5"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateAugust302021Member" xlink:label="loc_mtaff_ExpiryDateAugust302021Member_6"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ExpiryDateDomain" xlink:label="loc_mtaff_ExpiryDateDomain_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_WarrantsExercisePrice" xlink:label="loc_mtaff_WarrantsExercisePrice_11"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NumberOfOutstandingWarrants" xlink:label="loc_mtaff_NumberOfOutstandingWarrants_12"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_ScheduleOfWarrantLineItems_0" xlink:to="loc_mtaff_ScheduleOfWarrantTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_ScheduleOfWarrantTable_1" xlink:to="loc_mtaff_ExpiryDateAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_ExpiryDateAxis_1" xlink:to="loc_mtaff_ExpiryDateDomain_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateNovember082020Member_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateDecember212020Member_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateDecember212020OneMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateJanuary042021Member_4" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateJanuary042021OneMember_5" order="40" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ExpiryDateDomain_1" xlink:to="loc_mtaff_ExpiryDateAugust302021Member_6" order="50" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_ExpiryDateAxis_1" xlink:to="loc_mtaff_ExpiryDateDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ScheduleOfWarrantLineItems_0" xlink:to="loc_mtaff_WarrantsExercisePrice_11" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_ScheduleOfWarrantLineItems_0" xlink:to="loc_mtaff_NumberOfOutstandingWarrants_12" order="20" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfTransactionsBetweenRelatedPartiesDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems" xlink:label="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable" xlink:label="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_CategoriesOfRelatedPartiesAxis" xlink:label="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_KeyManagementPersonnelOfEntityOrParentMember" xlink:label="loc_ifrs-full_KeyManagementPersonnelOfEntityOrParentMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DirectorsMember" xlink:label="loc_mtaff_DirectorsMember_2"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForRelatedPartiesMember" xlink:label="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits" xlink:label="loc_ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_KeyManagementPersonnelCompensationSharebasedPayment" xlink:label="loc_ifrs-full_KeyManagementPersonnelCompensationSharebasedPayment_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_KeyManagementPersonnelCompensation" xlink:label="loc_ifrs-full_KeyManagementPersonnelCompensation_9"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesTable_1" xlink:to="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" xlink:to="loc_ifrs-full_KeyManagementPersonnelOfEntityOrParentMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_1" xlink:to="loc_mtaff_DirectorsMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_CategoriesOfRelatedPartiesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForRelatedPartiesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_KeyManagementPersonnelCompensationShorttermEmployeeBenefits_7" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_KeyManagementPersonnelCompensationSharebasedPayment_8" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems_0" xlink:to="loc_ifrs-full_KeyManagementPersonnelCompensation_9" order="30" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfSignificantTemporaryDifferencesUnusedTaxCreditsAndUnusedTaxLossesDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems" xlink:label="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable" xlink:label="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis" xlink:label="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember" xlink:label="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_MineralExpendituresAndCapitalAssetsMember" xlink:label="loc_mtaff_MineralExpendituresAndCapitalAssetsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_ShareIssueCostsMember" xlink:label="loc_mtaff_ShareIssueCostsMember_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_NonCapitalLossesAndOtherMember" xlink:label="loc_mtaff_NonCapitalLossesAndOtherMember_3"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember" xlink:label="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DeferredTaxAssetsAndLiabilitiesAbstract" xlink:label="loc_ifrs-full_DeferredTaxAssetsAndLiabilitiesAbstract_8"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_DeferredTaxAssetsAbstract" xlink:label="loc_mtaff_DeferredTaxAssetsAbstract_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised" xlink:label="loc_ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised_8"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsTable_1" xlink:to="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis_1" xlink:to="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1" xlink:to="loc_mtaff_MineralExpendituresAndCapitalAssetsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1" xlink:to="loc_mtaff_ShareIssueCostsMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_1" xlink:to="loc_mtaff_NonCapitalLossesAndOtherMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis_1" xlink:to="loc_ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems_0" xlink:to="loc_ifrs-full_DeferredTaxAssetsAndLiabilitiesAbstract_8" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DeferredTaxAssetsAndLiabilitiesAbstract_8" xlink:to="loc_mtaff_DeferredTaxAssetsAbstract_8" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_DeferredTaxAssetsAbstract_8" xlink:to="loc_ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised_8" order="0" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/REVENUEDetails">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RevenueLineItems" xlink:label="loc_mtaff_RevenueLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RevenueTable" xlink:label="loc_mtaff_RevenueTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_SignificantInvestmentsInSubsidiariesAxis" xlink:label="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForSubsidiariesMember" xlink:label="loc_ifrs-full_EntitysTotalForSubsidiariesMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_COSERoyaltyMember" xlink:label="loc_mtaff_COSERoyaltyMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_JoaquinRoyaltyMember" xlink:label="loc_mtaff_JoaquinRoyaltyMember_2"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_EntitysTotalForSubsidiariesMember" xlink:label="loc_ifrs-full_EntitysTotalForSubsidiariesMember_Default"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_RevenueFromStreamInterest" xlink:label="loc_mtaff_RevenueFromStreamInterest_7"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_RevenueFromRoyalties" xlink:label="loc_ifrs-full_RevenueFromRoyalties_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_Revenue" xlink:label="loc_ifrs-full_Revenue_9"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_RevenueLineItems_0" xlink:to="loc_mtaff_RevenueTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_RevenueTable_1" xlink:to="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForSubsidiariesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForSubsidiariesMember_1" xlink:to="loc_mtaff_COSERoyaltyMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_EntitysTotalForSubsidiariesMember_1" xlink:to="loc_mtaff_JoaquinRoyaltyMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_SignificantInvestmentsInSubsidiariesAxis_1" xlink:to="loc_ifrs-full_EntitysTotalForSubsidiariesMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_RevenueLineItems_0" xlink:to="loc_mtaff_RevenueFromStreamInterest_7" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_RevenueLineItems_0" xlink:to="loc_ifrs-full_RevenueFromRoyalties_8" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_RevenueLineItems_0" xlink:to="loc_ifrs-full_Revenue_9" order="30" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/ScheduleOfInformationRelatedToContractualObligationsDetail">
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CommitmentsLineItems" xlink:label="loc_mtaff_CommitmentsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_CommitmentsTable" xlink:label="loc_mtaff_CommitmentsTable_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ClassesOfFinancialInstrumentsAxis" xlink:label="loc_ifrs-full_ClassesOfFinancialInstrumentsAxis_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ClassesOfFinancialInstrumentsMember" xlink:label="loc_ifrs-full_ClassesOfFinancialInstrumentsMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_TradeAndOtherPayablesMember" xlink:label="loc_mtaff_TradeAndOtherPayablesMember_1"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_LoanCommitmentsMember" xlink:label="loc_ifrs-full_LoanCommitmentsMember_2"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AcquisitionsOfRoyaltiesAndStreamsMember" xlink:label="loc_mtaff_AcquisitionsOfRoyaltiesAndStreamsMember_3"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_OtherCommitmentMember" xlink:label="loc_mtaff_OtherCommitmentMember_4"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ClassesOfFinancialInstrumentsMember" xlink:label="loc_ifrs-full_ClassesOfFinancialInstrumentsMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_MaturityAxis" xlink:label="loc_ifrs-full_MaturityAxis_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_AggregatedTimeBandsMember" xlink:label="loc_ifrs-full_AggregatedTimeBandsMember_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_NotLaterThanOneYearMember" xlink:label="loc_ifrs-full_NotLaterThanOneYearMember_8"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_LaterThanOneYearAndNotLaterThanThreeYearsMember" xlink:label="loc_ifrs-full_LaterThanOneYearAndNotLaterThanThreeYearsMember_9"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_LaterThanThreeYearsAndNotLaterThanFiveYearsMember" xlink:label="loc_ifrs-full_LaterThanThreeYearsAndNotLaterThanFiveYearsMember_10"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_LaterThanFiveYearsMember" xlink:label="loc_ifrs-full_LaterThanFiveYearsMember_11"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_AggregatedTimeBandsMember" xlink:label="loc_ifrs-full_AggregatedTimeBandsMember_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_ContractualCapitalCommitments" xlink:label="loc_ifrs-full_ContractualCapitalCommitments_16"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_mtaff_CommitmentsLineItems_0" xlink:to="loc_mtaff_CommitmentsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_CommitmentsTable_1" xlink:to="loc_ifrs-full_ClassesOfFinancialInstrumentsAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsAxis_1" xlink:to="loc_ifrs-full_ClassesOfFinancialInstrumentsMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsMember_1" xlink:to="loc_mtaff_TradeAndOtherPayablesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsMember_1" xlink:to="loc_ifrs-full_LoanCommitmentsMember_2" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsMember_1" xlink:to="loc_mtaff_AcquisitionsOfRoyaltiesAndStreamsMember_3" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsMember_1" xlink:to="loc_mtaff_OtherCommitmentMember_4" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_ClassesOfFinancialInstrumentsAxis_1" xlink:to="loc_ifrs-full_ClassesOfFinancialInstrumentsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_mtaff_CommitmentsTable_1" xlink:to="loc_ifrs-full_MaturityAxis_8" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ifrs-full_MaturityAxis_8" xlink:to="loc_ifrs-full_AggregatedTimeBandsMember_8" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AggregatedTimeBandsMember_8" xlink:to="loc_ifrs-full_NotLaterThanOneYearMember_8" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AggregatedTimeBandsMember_8" xlink:to="loc_ifrs-full_LaterThanOneYearAndNotLaterThanThreeYearsMember_9" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AggregatedTimeBandsMember_8" xlink:to="loc_ifrs-full_LaterThanThreeYearsAndNotLaterThanFiveYearsMember_10" order="20" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_AggregatedTimeBandsMember_8" xlink:to="loc_ifrs-full_LaterThanFiveYearsMember_11" order="30" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ifrs-full_MaturityAxis_8" xlink:to="loc_ifrs-full_AggregatedTimeBandsMember_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_CommitmentsLineItems_0" xlink:to="loc_ifrs-full_ContractualCapitalCommitments_16" order="10" use="optional"/>
  </definitionLink>
  <definitionLink xlink:type="extended" xlink:role="http://www.metallaroyalty.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESDetails">
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsLineItems" xlink:label="loc_ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsLineItems_0"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsTable" xlink:label="loc_ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsTable_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AdoptionOfIFRS16LeasesAxis" xlink:label="loc_mtaff_AdoptionOfIFRS16LeasesAxis_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AdoptionOfIFRS16LeasesDomain" xlink:label="loc_mtaff_AdoptionOfIFRS16LeasesDomain_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AdoptionOfIFRS16LeasesMember" xlink:label="loc_mtaff_AdoptionOfIFRS16LeasesMember_1"/>
    <loc xlink:type="locator" xlink:href="mtaff-20200531.xsd#mtaff_AdoptionOfIFRS16LeasesDomain" xlink:label="loc_mtaff_AdoptionOfIFRS16LeasesDomain_Default"/>
    <loc xlink:type="locator" xlink:href="http://xbrl.ifrs.org/taxonomy/2019-03-27/full_ifrs/full_ifrs-cor_2019-03-27.xsd#ifrs-full_RightofuseAssets" xlink:label="loc_ifrs-full_RightofuseAssets_6"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsLineItems_0" xlink:to="loc_ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsTable_1" order="0" use="optional" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsTable_1" xlink:to="loc_mtaff_AdoptionOfIFRS16LeasesAxis_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtaff_AdoptionOfIFRS16LeasesAxis_1" xlink:to="loc_mtaff_AdoptionOfIFRS16LeasesDomain_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtaff_AdoptionOfIFRS16LeasesDomain_1" xlink:to="loc_mtaff_AdoptionOfIFRS16LeasesMember_1" order="0" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtaff_AdoptionOfIFRS16LeasesAxis_1" xlink:to="loc_mtaff_AdoptionOfIFRS16LeasesDomain_Default" order="10" use="optional"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ifrs-full_DisclosureOfQuantitativeInformationAboutRightofuseAssetsLineItems_0" xlink:to="loc_ifrs-full_RightofuseAssets_6" order="10" use="optional"/>
  </definitionLink>
</linkbase>