Source : WordNet®

Mononychus olecranus
     n : 75-million-year-old turkey-sized long-legged fossil found in
         the Gobi Desert having birdlike fused wrist bones and
         keeled breastbone and a long tail resembling a
         dinosaur's; short 3-inch-long forelimbs end in a single
         claw instead of wings; classification as bird or dinosaur
         is in dispute