Retain, v. t. [imp. & p. p. Retained; p. pr. & vb. n. Retaining.]
Etymology: [F. retainir, L. retinere; pref. re- re- + tenere to hold, keep. See Tenable, and cf. Rein of a bridle, Retention, Retinue.]
1. To continue to hold; to keep in possession; not to lose, part with, or dismiss; to retrain from departure, escape, or the like. "Thy shape invisibleretain." Shak. Be obedient, and retain Unalterably firm his love entire. Milton. An executor may retain a debt due to him from the testator. Blackstone.
2. To keep in pay; to employ by a preliminary fee paid; to hire; to engage; as, to retain a counselor. A Benedictine convent has now retained the most learned father of their order to write in its defense. Addison.
3. To restrain; to prevent. [Obs.] Sir W. Temple. Retaining wall (Arch. & Engin.), a wall built to keep any movable backing, or a bank of sand or earth, in its place; -- called also retain wall.
Syn. -- To keep; hold; retrain. See Keep.
1 other Webster entry under this spelling
Retain, v. i.
1. To belong; to pertain. [Obs.] A somewhat languid relish, retaining to bitterness. Boyle.
2. To keep; to continue; to remain. [Obs.] Donne.
Shades of meaning
Fernald has no entry of its own for retain; he lists it under keep.
He lists it without comment; the entries above explain its neighbors.