The Collaborative International Dictionary of English v.0.48:

Redwing \Red"wing`\ (-w?ng`), n. (Zool.)
   A European thrush (Turdus iliacus). Its under wing coverts
   are orange red. Called also redwinged thrush.
   (b) A North American passerine bird (Agelarius
       ph[oe]niceus) of the family Icteridae. The male is
       black, with a conspicuous patch of bright red, bordered
       with orange, on each wing. Called also redwinged
       blackbird, red-winged troupial, marsh blackbird, and
       swamp blackbird.
       [1913 Webster]

WordNet (r) 3.0 (2006):

redwing
    n 1: North American blackbird with scarlet patches on the wings
         [syn: red-winged blackbird, redwing, Agelaius
         phoeniceus]
    2: small European thrush having reddish flanks [syn: redwing,
       Turdus iliacus]