Twin | Webster's Dictionary (1865)

Twin, n.

noun

[A-S. twīn, double, from twi, two, getwinne, pl., twins; O. H. Ger. zwienling, N. H. Ger. zwilling, a twin. See TWIBIL, and cf. TWINE.]

Sense 1. One of two produced at a birth, especially by an animal that ordinarily brings forth but one at a birth;—used chiefly in the plural, and applied to the young of beasts, as well as of human beings.

Sense 2. (pl.) (Astron.) A constellation and sign of the zodiac; Gemini.

Sense 3. One very much resembling another.

Twin, a.

adjective

Being one of two born at a birth; as, a twin brother or sister.
Being one of a pair much resembling one another; standing in the relation of a twin to something else; — often followed by to.
(Bot.) Swelling out into two protuberances, as an anther or germ. Martyn.
(Min.) Composed of two united crystals.

Twin, v. i.

verbintransitive

To bring forth two at a birth. Tusser.
To be born at the same birth. Shak.
To be paired; to be suited. [Rare.]

Still we moved Together, twinned, as horse's ear and eye. Tennyson.

Twin, v. t. & i.

verbtransitiveintransitive

To separate into two parts; to divide. [Obs.] Chaucer.