tunic

Concise Oxford English Dictionary © 2008 Oxford University Press:
tunic/ˈtjuːnɪk/

▶noun

• 1 a loose sleeveless garment reaching to the thigh or knees.

  ■ a gymslip.

• 2 a close-fitting short coat worn as part of a uniform.

• 3 Biology & Anatomy an integument or membrane enclosing or lining an organ or part.

  ■ Botany any of the concentric layers of a plant bulb, e.g. an onion.

– origin OE, from OFr. tunique or L. tunica.