Search Result for "protoavis": 
Wordnet 3.0

NOUN (1)

1. most primitive avian type known; extinct bird of the Triassic having bird-like jaw and hollow limbs and breastbone with dinosaur-like tail and hind limbs; 



WordNet (r) 3.0 (2006):

protoavis
    n 1: most primitive avian type known; extinct bird of the
         Triassic having bird-like jaw and hollow limbs and
         breastbone with dinosaur-like tail and hind limbs