[ ti-ran-uh-sawr, tahy- ]
/ tɪˈræn əˌsɔr, taɪ- /


a large, carnivorous dinosaur, Tyrannosaurus rex, from the Late Cretaceous Epoch of North America, that walked erect on its hind feet.

Origin of tyrannosaur

< New Latin Tyrannosaurus (1905), equivalent to Greek tyranno- (combining form representing týrannos tyrant) + saûros -saur

Can be confused

tyrannous tyrannosaur
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for tyrannosaur

  • Olivia Colman delivers a devastating performance as an abuse victim in the indie film Tyrannosaur.

  • Kirk grimaced and DeVore saw a faint image of a tyrannosaur, which reared up, jaws agape.

    Final Weapon|Everett B. Cole
  • It is somewhat older than the Tyrannosaur although still of the late Cretacic period, and may have been ancestral to it.

    Dinosaurs|William Diller Matthew
  • The largest of these grew to be 30 feet long and 15 to 20 feet high, comparable, therefore, to the tyrannosaur in size.

    Geology|William J. Miller

Science definitions for tyrannosaur


[ tĭ-rănə-sôr′ ]

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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