tunic

n. woman's long upper garment; loose-fitting garment often without sleeves and often belted (worn in ancient Greece and Rome); enclosing membrane, covering (Zoology, Anatomy, Botany)

The tunic (Latin tunica) was the common masculine garment of Greco-Roman civilization. It was worn by citizens and non-citizens alike; citizens, though, would wear it under the toga, especially at formal occasions. The length of the garment, the presence or lack of stripes, as well as their width and ornamentation, would indicate the wearer's status in Roman society. Soldiers, slaves and manual workers generally had tunics to a little above the knee; those in more sedentary occupations to about the ankle (unless they were expecting to ride a horse, when a shorter one would be worn).
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Tu·nic n. A coat or layer enveloping an organ or a part; tunica. tunic a covering or coat. See also tunica. [more]Tunic - Community and Resources

Noun
1. an enveloping or covering membrane or layer of body tissue
(synonym) tunica, adventitia
(hypernym) membrane, tissue layer
(hyponym) albuginea
2. any of a variety of loose fitting cloaks extending to the hips or knees
(hypernym) cloak
(hyponym) chiton

(n.)
See Mantle, n., 3 (a).
  

(n.)
Same as Tunicle.
  

(n.)
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.
  

(n.)
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.
  

(n.)
A natural covering; an integument; as, the tunic of a seed.
  

(n.)
A membrane, or layer of tissue, especially when enveloping an organ or part, as the eye.