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ădoptātĭo, ōnis, f. [id.; access. form of adoptio, by which it was supplanted after the class. per.], an adopting, receiving as a child, υἱοθεσία: quid propagatio nominis, quid adoptationes filiorum, Cic. Tusc. 1, 14, 31: adoptatio Theophani agitata est, id. Balb. 25, 57: ipsum illum adoptatione in regnum pervenisse, Sall. J. 11, 6: quod per praetorem fit, adoptatio dicitur; quod per populum, arrogatio, Gell. 5, 19; Tert. adv. Gent. 2, 1.