Ornitholestes, awr nih thuh LEHS teez, was a small meat-eating dinosaur that lived about 150 million years ago, during the Late Jurassic Period. Its name comes from the Greek words for bird and robber. Scientists once believed this dinosaur hunted mainly birds. Ornitholestes belonged to a group of dinosaurs called coelurosaurs, from which birds may have evolved. Coelurosaurs, in turn, belonged to a larger dinosaur group called theropods.