Wordnet 3.0
NOUN (1)
1.
a turkey-sized long-legged fossil 75 million years old found in the Gobi Desert having bird-like fused wrist bones and keeled breastbone and a long tail resembling a dinosaur's;
short forelimbs end in a single claw instead of wings;
classification as bird or dinosaur is in dispute;
WordNet (r) 3.0 (2006):
Mononychus olecranus
n 1: a turkey-sized long-legged fossil 75 million years old
found in the Gobi Desert having bird-like fused wrist bones
and keeled breastbone and a long tail resembling a
dinosaur's; short forelimbs end in a single claw instead of
wings; classification as bird or dinosaur is in dispute