Source : Webster's Revised Unabridged Dictionary (1913)

Redbird \Red"bird`\ (-b?rd`), n. (Zo["o]l.)
   (a) The cardinal bird.
   (b) The summer redbird ({Piranga rubra}).
   (c) The scarlet tanager. See {Tanager}.

Source : WordNet®

redbird
     n 1: the male is bright red with black wings and tail [syn: {scarlet
          tanager}, {Piranga olivacea}, {firebird}]
     2: crested thick-billed North American finch having bright red
        plumage in the male [syn: {cardinal}, {cardinal grosbeak},
         {Richmondena Cardinalis}, {Cardinalis cardinalis}]