Unicorn

n.
  1. A fabulous animal with one horn; the monoceros; -- often represented in heraldry as a supporter.
  2. A two-horned animal of some unknown kind, so called in the Authorized Version of the Scriptures.
  3. (Zoöl.) The kamichi; -- called also unicorn bird.
  4. (Mil.) A howitzer.
    1. Any large beetle having a hornlike prominence on the head or prothorax.
    2. The larva of a unicorn moth.
    Fossil unicorn, or Fossil unicorn's horn (Med.),
    a substance formerly of great repute in medicine; -- named from having been supposed to be the bone or the horn of the unicorn.
    Unicorn fish, Unicorn whale (Zoöl.),
    the narwhal.
    Unicorn moth (Zoöl.),
    a notodontian moth (Cœlodasys unicornis) whose caterpillar has a prominent horn on its back; -- called also unicorn prominent.
    Unicorn root (Bot.),
    a name of two North American plants, the yellow-flowered colicroot (Aletris farinosa) and the blazing star (Chamælirium luteum). Both are used in medicine.
    Unicorn shell (Zoöl.),
    any one of several species of marine gastropods having a prominent spine on the lip of the shell. Most of them belong to the genera Monoceros and Leucozonia.