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.