a large, carnivorous dinosaur, Tyrannosaurus rex, from the Late Cretaceous Epoch of North America, that walked erect on its hind feet.
- tyrannous, tyrannosaur
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Scientific definitions for tyrannosaur
Any of various very large carnivorous dinosaurs of the genus Tyrannosaurus and related genera of the Cretaceous Period. Tyrannosaurs had very small forelimbs and a large head with sharp teeth. They walked on two legs, probably bent forward with their long tail stretched out as a counterbalance. Tyrannosaurs were theropods and probably distantly related to birds. The largest species, T. rex, grew to lengths of 14.3 m (47 ft) or more and may have been the largest land predator that ever lived.
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