The Collaborative International Dictionary of English v.0.48:

Tinamou \Tin"a*mou\, n. [From the native name: cf. F. tinamous.]
   (Zool.)
   Any one of several species of South American birds belonging
   to Tinamus and allied genera.
   [1913 Webster]

   Note: In general appearance and habits they resemble grouse
         and partridges, but in anatomical characters they are
         allied to the ostriches and other struthious birds.
         Their wings are of moderate length, and they are able
         to fly a considerable distance.
         [1913 Webster]

WordNet (r) 3.0 (2006):

tinamou
    n 1: heavy-bodied small-winged South American game bird
         resembling a gallinaceous bird but related to the ratite
         birds [syn: tinamou, partridge]