Mustache

n. pl. Mustaches ().
  1. That part of the beard which grows on the upper lip; hair left growing above the mouth.
  2. (Zoöl.) A West African monkey (Cercopithecus cephus). It has yellow whiskers, and a triangular blue mark on the nose.
  3. (Zoöl.) Any conspicuous stripe of color on the side of the head, beneath the eye of a bird.
  4. A stain or discoloration on the upper lip of a person; as, wearing a milk mustache.