Source : Webster's Revised Unabridged Dictionary (1913)

Plica \Pli"ca\, n. [LL., a fold, fr. L. plicare to fold. See
   {Ply}, v.]
   1. (Med.) A disease of the hair (Plica polonica), in which it
      becomes twisted and matted together. The disease is of
      Polish origin, and is hence called also {Polish plait}.
      --Dunglison.

   2. (Bot.) A diseased state in plants in which there is an
      excessive development of small entangled twigs, instead of
      ordinary branches.

   3. (Zo["o]l.) The bend of the wing of a bird.

Source : WordNet®

plica
     n : a folded part (as a fold of skin or muscle) [syn: {fold}]
     [also: {plicae} (pl)]