Source : Webster's Revised Unabridged Dictionary (1913)

Passerine \Pas"ser*ine\, a. [L. passerinus, fr. passer a
   sparrow.] (Zo["o]l.)
   Of or pertaining to the Passeres.

         The columbine, gallinaceous, and passerine tribes
         people the fruit trees.                  --Sydney
                                                  Smith.

Passerine \Pas"ser*ine\, n. (Zo["o]l.)
   One of the Passeres.

Source : WordNet®

passerine
     adj : relating to or characteristic of the passeriform birds [ant:
            {nonpasserine}]
     n : perching birds mostly small and living near the ground with
         feet having 4 toes arranged to allow for gripping the
         perch; most are songbirds; hatchlings are helpless [syn:
         {passeriform bird}]