The Collaborative International Dictionary of English v.0.48:

Hangbird \Hang"bird`\ (h[a^]ng"b[~e]rd`), n. (Zool.)
   The Baltimore oriole (Icterus galbula); -- so called
   because its nest is suspended from the limb of a tree. See
   Baltimore oriole.
   [1913 Webster]

WordNet (r) 3.0 (2006):

hangbird
    n 1: eastern subspecies of northern oriole [syn: Baltimore
         oriole, Baltimore bird, hangbird, firebird, Icterus
         galbula galbula]