Adoptive

google

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late Middle English: via Old French from Latin adoptivus, from adoptare ‘select for oneself’ (see adopt).

wiktionary

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adopt +‎  -ive

etymonline

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adoptive (adj.)

early 15c., adpotif, "by adoption," from Old French adoptif and directly from Latin adoptivus "pertaining to adoption," from stem of adoptere "to choose, adopt" (see adopt).