Source : Webster's Revised Unabridged Dictionary (1913)

Beard \Beard\, n. [OE. berd, AS. beard; akin to Fries. berd, D.
   baard, G. bart, Lith. barzda, OSlav. brada, Pol. broda, Russ.
   boroda, L. barba, W. barf. Cf. 1st {Barb}.]
   1. The hair that grows on the chin, lips, and adjacent parts
      of the human face, chiefly of male adults.

   2. (Zo["o]l.)
      (a) The long hairs about the face in animals, as in the
          goat.
      (b) The cluster of small feathers at the base of the beak
          in some birds
      (c) The appendages to the jaw in some Cetacea, and to the
          mouth or jaws of some fishes.
      (d) The byssus of certain shellfish, as the muscle.
      (e) The gills of some bivalves, as the oyster.
      (f) In insects, the hairs of the labial palpi of moths and
          butterflies.

   3. (Bot.) Long or stiff hairs on a plant; the awn; as, the
      beard of grain.

   4. A barb or sharp point of an arrow or other instrument,
      projecting backward to prevent the head from being easily
      drawn out.

   5. That part of the under side of a horse's lower jaw which
      is above the chin, and bears the curb of a bridle.

   6. (Print.) That part of a type which is between the shoulder
      of the shank and the face.

   7. An imposition; a trick. [Obs.] --Chaucer.

   {Beard grass} (Bot.), a coarse, perennial grass of different
      species of the genus {Andropogon}.

   {To one's beard}, to one's face; in open defiance.