Source : Webster's Revised Unabridged Dictionary (1913)

Egret \E"gret\, n. [See {Aigret}, {Heron}.]
   1. (Zo["o]l.) The name of several species of herons which
      bear plumes on the back. They are generally white. Among
      the best known species are the American egret ({Ardea, or
      Herodias, egretta}); the great egret ({A. alba}); the
      little egret ({A. garzetta}), of Europe; and the American
      snowy egret ({A. candidissima}).

            A bunch of egrets killed for their plumage. --G. W.
                                                  Cable.

   2. A plume or tuft of feathers worn as a part of a headdress,
      or anything imitating such an ornament; an aigrette.

   3. (Bot.) The flying feathery or hairy crown of seeds or
      achenes, as the down of the thistle.

   4. (Zo["o]l.) A kind of ape.

Source : WordNet®

egret
     n : any of various usually white herons having long plumes
         during breeding season