The Collaborative International Dictionary of English v.0.48:

Passeres \Pas"se*res\, prop. n. pl. [NL., fr. L. passer a
   sparrow.] (Zool.)
   An order, or suborder, of birds, including more that half of
   all the known species. It embraces all singing birds
   (Oscines), together with many other small perching birds.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Passeres
    n 1: two names for the suborder of typical songbirds [syn:
         Oscines, suborder Oscines, Passeres, suborder
         Passeres]