Source : Webster's Revised Unabridged Dictionary (1913)

Retriever \Re*triev"er\, n.
   1. One who retrieves.

   2. (Zo["o]l.) A dor, or a breed of dogs, chiefly employed to
      retrieve, or to find and recover game birds that have been
      killed or wounded.

Source : WordNet®

retriever
     n : a dog with heavy water-resistant coat that can be trained to
         retrieve game