<?xml version="1.0" encoding="US-ASCII" standalone="no"?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 6.5a -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: https://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrli="http://www.xbrl.org/2003/instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingsByIndustrySector" roleURI="http://xbrl.sec.gov/oef/role/HoldingsByIndustrySector" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingsByGeographicRegion" roleURI="http://xbrl.sec.gov/oef/role/HoldingsByGeographicRegion" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingsByCreditQuality" roleURI="http://xbrl.sec.gov/oef/role/HoldingsByCreditQuality" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingsByMaturity" roleURI="http://xbrl.sec.gov/oef/role/HoldingsByMaturity" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingsByAssetCategory" roleURI="http://xbrl.sec.gov/oef/role/HoldingsByAssetCategory" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingsByOtherCategory" roleURI="http://xbrl.sec.gov/oef/role/HoldingsByOtherCategory" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingsByOtherCategory2" roleURI="http://xbrl.sec.gov/oef/role/HoldingsByOtherCategory2" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#LargestHoldings" roleURI="http://xbrl.sec.gov/oef/role/LargestHoldings" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#ProspectusOnly" roleURI="http://xbrl.sec.gov/rr/role/ProspectusOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#RiskOnly" roleURI="http://xbrl.sec.gov/rr/role/RiskOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#CoregistrantOnly" roleURI="http://xbrl.sec.gov/oef/role/CoregistrantOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#SeriesOnly" roleURI="http://xbrl.sec.gov/oef/role/SeriesOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#ClassOnly" roleURI="http://xbrl.sec.gov/oef/role/ClassOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#PerformanceMeasureOnly" roleURI="http://xbrl.sec.gov/rr/role/PerformanceMeasureOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingAssetCategoryOnly" roleURI="http://xbrl.sec.gov/oef/role/HoldingAssetCategoryOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#BroadBasedIndexOnly" roleURI="http://xbrl.sec.gov/oef/role/BroadBasedIndexOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#AdditionalIndexOnly" roleURI="http://xbrl.sec.gov/oef/role/AdditionalIndexOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#IndustrySectorOnly" roleURI="http://xbrl.sec.gov/oef/role/IndustrySectorOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#GeographicRegionOnly" roleURI="http://xbrl.sec.gov/oef/role/GeographicRegionOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#CreditQualityOnly" roleURI="http://xbrl.sec.gov/oef/role/CreditQualityOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#MaturityOnly" roleURI="http://xbrl.sec.gov/oef/role/MaturityOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#Other1CategoryOnly" roleURI="http://xbrl.sec.gov/oef/role/Other1CategoryOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#Other2CategoryOnly" roleURI="http://xbrl.sec.gov/oef/role/Other2CategoryOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#LargestHoldingOnly" roleURI="http://xbrl.sec.gov/oef/role/LargestHoldingOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#SalesLoadOnly" roleURI="http://xbrl.sec.gov/oef/role/SalesLoadOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#HoldingMeasureOnly" roleURI="http://xbrl.sec.gov/oef/role/HoldingMeasureOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#ValueMeasureOnly" roleURI="http://xbrl.sec.gov/oef/role/ValueMeasureOnly" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" arcroleURI="http://xbrl.org/int/dim/arcrole/all" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#notAll" arcroleURI="http://xbrl.org/int/dim/arcrole/notAll" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/rr/role/ProspectusOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/rr/role/RiskOnly">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_AllRisksMember" xlink:label="loc_oefAllRisksMember" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_AssetConcentrationRiskMember" xlink:label="loc_avitAssetConcentrationRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitAssetConcentrationRiskMember" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_ConflictsOfInterestRiskMember" xlink:label="loc_avitConflictsOfInterestRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitConflictsOfInterestRiskMember" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_EtfRisksMember" xlink:label="loc_avitEtfRisksMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitEtfRisksMember" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_FixedIncomeSecuritiesRiskMember" xlink:label="loc_avitFixedIncomeSecuritiesRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitFixedIncomeSecuritiesRiskMember" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_FixedIncomeUnderlyingEtfRisksMember" xlink:label="loc_avitFixedIncomeUnderlyingEtfRisksMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitFixedIncomeUnderlyingEtfRisksMember" xlink:type="arc" order="40" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_FundOfFundsRisksMember" xlink:label="loc_avitFundOfFundsRisksMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitFundOfFundsRisksMember" xlink:type="arc" order="50" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_ManagementRiskMember" xlink:label="loc_avitManagementRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitManagementRiskMember" xlink:type="arc" order="60" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_MarketRiskMember" xlink:label="loc_avitMarketRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitMarketRiskMember" xlink:type="arc" order="70" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_MarketTimingRiskMember" xlink:label="loc_avitMarketTimingRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitMarketTimingRiskMember" xlink:type="arc" order="80" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_NonFixedIncomeUnderlyingEtfRisksMember" xlink:label="loc_avitNonFixedIncomeUnderlyingEtfRisksMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitNonFixedIncomeUnderlyingEtfRisksMember" xlink:type="arc" order="90" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_NonUSSecuritiesRiskMember" xlink:label="loc_avitNonUSSecuritiesRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitNonUSSecuritiesRiskMember" xlink:type="arc" order="100" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_EquitySecuritiesRiskMember" xlink:label="loc_avitEquitySecuritiesRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitEquitySecuritiesRiskMember" xlink:type="arc" order="110" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_CanadianInvestmentRiskMember" xlink:label="loc_avitCanadianInvestmentRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitCanadianInvestmentRiskMember" xlink:type="arc" order="120" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_ConcentrationRiskMember" xlink:label="loc_avitConcentrationRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitConcentrationRiskMember" xlink:type="arc" order="130" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_IndustrySpecificRisksMember" xlink:label="loc_avitIndustrySpecificRisksMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitIndustrySpecificRisksMember" xlink:type="arc" order="140" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_InvestmentRiskMember" xlink:label="loc_avitInvestmentRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitInvestmentRiskMember" xlink:type="arc" order="150" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_IssuerSpecificRiskMember" xlink:label="loc_avitIssuerSpecificRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitIssuerSpecificRiskMember" xlink:type="arc" order="160" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_LargeCapMidCapAndSmallCapCompaniesRiskMember" xlink:label="loc_avitLargeCapMidCapAndSmallCapCompaniesRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitLargeCapMidCapAndSmallCapCompaniesRiskMember" xlink:type="arc" order="170" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_MlpRiskMember" xlink:label="loc_avitMlpRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitMlpRiskMember" xlink:type="arc" order="180" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_MlpTaxRiskMember" xlink:label="loc_avitMlpTaxRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitMlpTaxRiskMember" xlink:type="arc" order="190" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_PficTaxRiskMember" xlink:label="loc_avitPficTaxRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitPficTaxRiskMember" xlink:type="arc" order="200" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_ReplicationManagementRiskMember" xlink:label="loc_avitReplicationManagementRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitReplicationManagementRiskMember" xlink:type="arc" order="210" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_TrackingErrorRiskMember" xlink:label="loc_avitTrackingErrorRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitTrackingErrorRiskMember" xlink:type="arc" order="220" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_CurrencyRiskMember" xlink:label="loc_avitCurrencyRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitCurrencyRiskMember" xlink:type="arc" order="230" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_EmergingMarketsRiskMember" xlink:label="loc_avitEmergingMarketsRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitEmergingMarketsRiskMember" xlink:type="arc" order="240" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_ManagedPortfolioRiskMember" xlink:label="loc_avitManagedPortfolioRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitManagedPortfolioRiskMember" xlink:type="arc" order="250" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_PrivateEquityRiskMember" xlink:label="loc_avitPrivateEquityRiskMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefAllRisksMember" xlink:to="loc_avitPrivateEquityRiskMember" xlink:type="arc" order="260" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/CoregistrantOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/SeriesOnly">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityDomain" xlink:label="loc_deiEntityDomain" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_S000015810Member" xlink:label="loc_avitS000015810Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_avitS000015810Member" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_S000015812Member" xlink:label="loc_avitS000015812Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_avitS000015812Member" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_S000015809Member" xlink:label="loc_avitS000015809Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_avitS000015809Member" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_S000015811Member" xlink:label="loc_avitS000015811Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_avitS000015811Member" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_S000015808Member" xlink:label="loc_avitS000015808Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_avitS000015808Member" xlink:type="arc" order="40" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_S000040336Member" xlink:label="loc_avitS000040336Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_avitS000040336Member" xlink:type="arc" order="50" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_S000046802Member" xlink:label="loc_avitS000046802Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_deiEntityDomain" xlink:to="loc_avitS000046802Member" xlink:type="arc" order="60" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/ClassOnly">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_ShareClassDomain" xlink:label="loc_oefShareClassDomain" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043416Member" xlink:label="loc_avitC000043416Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043416Member" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043417Member" xlink:label="loc_avitC000043417Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043417Member" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043421Member" xlink:label="loc_avitC000043421Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043421Member" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043420Member" xlink:label="loc_avitC000043420Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043420Member" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043414Member" xlink:label="loc_avitC000043414Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043414Member" xlink:type="arc" order="40" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043415Member" xlink:label="loc_avitC000043415Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043415Member" xlink:type="arc" order="50" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043418Member" xlink:label="loc_avitC000043418Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043418Member" xlink:type="arc" order="60" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043419Member" xlink:label="loc_avitC000043419Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043419Member" xlink:type="arc" order="70" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043412Member" xlink:label="loc_avitC000043412Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043412Member" xlink:type="arc" order="80" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000043413Member" xlink:label="loc_avitC000043413Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000043413Member" xlink:type="arc" order="90" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000125262Member" xlink:label="loc_avitC000125262Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000125262Member" xlink:type="arc" order="100" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000125263Member" xlink:label="loc_avitC000125263Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000125263Member" xlink:type="arc" order="110" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000146220Member" xlink:label="loc_avitC000146220Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000146220Member" xlink:type="arc" order="120" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_C000146221Member" xlink:label="loc_avitC000146221Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefShareClassDomain" xlink:to="loc_avitC000146221Member" xlink:type="arc" order="130" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/rr/role/PerformanceMeasureOnly">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_PerformanceMeasureDomain" xlink:label="loc_oefPerformanceMeasureDomain" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index1Member" xlink:label="loc_avitIndex1Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex1Member" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index2Member" xlink:label="loc_avitIndex2Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex2Member" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index3Member" xlink:label="loc_avitIndex3Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex3Member" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index4Member" xlink:label="loc_avitIndex4Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex4Member" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index5Member" xlink:label="loc_avitIndex5Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex5Member" xlink:type="arc" order="40" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index6Member" xlink:label="loc_avitIndex6Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex6Member" xlink:type="arc" order="50" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index7Member" xlink:label="loc_avitIndex7Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex7Member" xlink:type="arc" order="60" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index8Member" xlink:label="loc_avitIndex8Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex8Member" xlink:type="arc" order="70" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index9Member" xlink:label="loc_avitIndex9Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex9Member" xlink:type="arc" order="80" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index10Member" xlink:label="loc_avitIndex10Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex10Member" xlink:type="arc" order="90" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index11Member" xlink:label="loc_avitIndex11Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex11Member" xlink:type="arc" order="100" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index12Member" xlink:label="loc_avitIndex12Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex12Member" xlink:type="arc" order="110" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index13Member" xlink:label="loc_avitIndex13Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex13Member" xlink:type="arc" order="120" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index14Member" xlink:label="loc_avitIndex14Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex14Member" xlink:type="arc" order="130" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index15Member" xlink:label="loc_avitIndex15Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex15Member" xlink:type="arc" order="140" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index16Member" xlink:label="loc_avitIndex16Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex16Member" xlink:type="arc" order="150" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index17Member" xlink:label="loc_avitIndex17Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex17Member" xlink:type="arc" order="160" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index18Member" xlink:label="loc_avitIndex18Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex18Member" xlink:type="arc" order="170" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index19Member" xlink:label="loc_avitIndex19Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex19Member" xlink:type="arc" order="180" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index20Member" xlink:label="loc_avitIndex20Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex20Member" xlink:type="arc" order="190" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index21Member" xlink:label="loc_avitIndex21Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex21Member" xlink:type="arc" order="200" />
      <link:loc xlink:type="locator" xlink:href="avit-20260430.xsd#avit_Index22Member" xlink:label="loc_avitIndex22Member" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_oefPerformanceMeasureDomain" xlink:to="loc_avitIndex22Member" xlink:type="arc" order="210" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/HoldingAssetCategoryOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/BroadBasedIndexOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/AdditionalIndexOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/IndustrySectorOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/GeographicRegionOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/CreditQualityOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/MaturityOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/Other1CategoryOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/Other2CategoryOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/LargestHoldingOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/SalesLoadOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/HoldingMeasureOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/ValueMeasureOnly" />
</link:linkbase>
