There is 1 meaning of the phrase
Mononychus Olecranus.
Mononychus Olecranus
- as a noun
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