Source : Webster's Revised Unabridged Dictionary (1913)

Lunule \Lu"nule\, n. [F., fr. L. lunula, dim. of luna moon.]
   1. (Anat.) Anything crescent-shaped; a crescent-shaped part
      or mark; a lunula, a lune.

   2. (Chem.) A lune. See {Lune}.

   3. (Zo["o]l.)
      (a) A small or narrow crescent.
      (b) A special area in front of the beak of many bivalve
          shells. It sometimes has the shape of a double
          crescent, but is oftener heart-shaped. See Illust. of
          {Bivalve}.

Source : WordNet®

lunule
     n : the crescent-shaped area at the base of the human fingernail
         [syn: {half-moon}, {lunula}]