Source : Webster's Revised Unabridged Dictionary (1913)

Beaver \Bea"ver\, n. [OE. bever, AS. beofer, befer; akin to D.
   bever, OHG. bibar, G. biber, Sw. b["a]fver, Dan. b[ae]ver,
   Lith. bebru, Russ. bobr', Gael. beabhar, Corn. befer, L.
   fiber, and Skr. babhrus large ichneumon; also as an adj.,
   brown, the animal being probably named from its color. ?253.
   See {Brown}.]
   1. (Zo["o]l.) An amphibious rodent, of the genus {Castor}.

   Note: It has palmated hind feet, and a broad, flat tail. It
         is remarkable for its ingenuity in constructing its
         valued for its fur, and for the material called castor,
         obtained from two small bags in the groin of the
         animal. The European species is {Castor fiber}, and the
         American is generally considered a variety of this,
         although sometimes called {Castor Canadensis}.

   2. The fur of the beaver.

   3. A hat, formerly made of the fur of the beaver, but now
      usually of silk.

            A brown beaver slouched over his eyes. --Prescott.

   4. Beaver cloth, a heavy felted woolen cloth, used chiefly
      for making overcoats.

   {Beaver rat} (Zo["o]l.), an aquatic ratlike quadruped of
      Tasmania ({Hydromys chrysogaster}).

   {Beaver skin}, the furry skin of the beaver.

   {Bank beaver}. See under 1st {Bank}.

Source : WordNet®

Castor fiber
     n : a European variety of beaver [syn: {Old World beaver}]