adoption (n.)

mid-14c., from Old French adopcion or directly from Late Latin adoptionem (nominative adoptio) "a taking as one's child," shorter form of adoptatio, noun of action from past-participle stem of Latin adoptare "chose for oneself, take by choice, select, adopt," especially "to take into a family, adopt as a child," from ad "to" (see ad-) + optare "choose, wish, desire," from PIE root *op- (2) "to choose" (see option (n.)).