\Tu"nic\, n. [L. tunica: cf. F. tunique.]
1. (Rom. Antiq.) An under-garment worn by the ancient Romans
   of both sexes. It was made with or without sleeves,
   reached to or below the knees, and was confined at the
   waist by a girdle.
2. Any similar garment worm by ancient or Oriental peoples;
   also, a common name for various styles of loose-fitting
   under-garments and over-garments worn in modern times by
   Europeans and others.
3. (R. C. Ch.) Same as {Tunicle}.
4. (Anat.) A membrane, or layer of tissue, especially when
   enveloping an organ or part, as the eye.
5. (Bot.) A natural covering; an integument; as, the tunic of
   a seed.
6. (Zo["o]l.) See {Mantle}, n., 3
   (a) .