Source : Webster's Revised Unabridged Dictionary (1913)

Wader \Wad"er\, n.
   1. One who, or that which, wades.

   2. (Zo["o]l.) Any long-legged bird that wades in the water in
      search of food, especially any species of limicoline or
      grallatorial birds; -- called also {wading bird}. See
      Illust. g, under {Aves}.

Source : WordNet®

wader
     n : any of many long-legged birds that wade in water in search
         of food [syn: {wading bird}]