\ ˈreks How to pronounce rex (audio) \
plural rexes or rex

Definition of rex

 (Entry 1 of 2)

: an animal (such as a domestic rabbit or cat) showing a genetic recessive variation in which the guard hairs are very short, sparse, or entirely lacking — compare cornish rex, devon rex


Latin noun
\ ˈreks How to pronounce rex (audio) \

Definition of rex (Entry 2 of 2)

: king

Illustration of rex

Illustration of rex


In the meaning defined above

Examples of rex in a Sentence

Recent Examples on the Web: Noun In a groundbreaking discovery, scientists found stronger evidence that the Tyrannosaurus rex may have traveled and hunted in packs — a topic which experts have debated for decades. Ashley Shaffer, USA TODAY, "Guilty of murder," 20 Apr. 2021 The print is believed to be from a species of theropod, which are carnivorous dinosaurs that stood on two legs, much like the Tyrannosaurus rex. Mike Wehner, BGR, "This massive dinosaur footprint was found completely by accident," 18 Apr. 2021 Only around 100 Tyrannosaurus rex fossils have been discovered since the species was described by American paleontologist Henry Fairfield Osborn in 1902. David Bressan, Forbes, "About 2.5 Billion T. Rex Dinosaurs Stomped Across The Earth’s Surface, Study Says," 16 Apr. 2021 Meanwhile at the Witte, two adults and one juvenile Alamosaurus tower over a Tyrannosaurus rex on a large mural, while a 10 ½-foot replica of an Alamosaurus leg dwarfs visitors. René A. Guzman, San Antonio Express-News, "The Alamosaurus was a Texas dinosaur and one of the world's largest. But no, it was not named after the Alamo. Boo.," 30 Mar. 2021 Ultimately, only two were built: a 45-foot-tall, 150-foot-long brontosaurus and a Tyrannosaurus rex named Mr. Rex. Los Angeles Times, "Today’s Headlines: ‘A nightmare in Boulder’," 23 Mar. 2021 The remains of a Tyrannosaurus rex were also found slightly overlapping with the Triceratops. Ashley Strickland, CNN, "'Dueling dinosaurs' fossils show Triceratops, T. rex, may have died after a battle," 17 Nov. 2020 Bone fragments gave away the presence of a big dinosaur, and, through an excavation carried out by the commercial fossil outfit Black Hills Institute in 1992, the fossil turned out to be a gorgeous Tyrannosaurus rex. Riley Black, Smithsonian Magazine, "A T. Rex Sold for $31.8 Million and Paleontologists Are Worried," 16 Oct. 2020 Last year, paleontologists in Canada touted the discovery of the world’s largest Tyrannosaurus rex. James Rogers, Fox News, "12-year-old boy makes 'significant' dinosaur discovery," 18 Oct. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rex.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of rex


1920, in the meaning defined above

History and Etymology for rex


modification of French castorrex, castorex, a variety of rabbit, perhaps from Latin castor beaver + rex king — more at castor, royal

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Last Updated

4 May 2021

Cite this Entry

“Rex.” Dictionary, Merriam-Webster, Accessed 8 May. 2021.

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