variants or less commonly T-Rex
plural T. rexes also T-Rexes
: tyrannosaurus rex
Though no one can actually time a running dinosaur with a stopwatch, scientists still have some idea of how fast T. rex and his companions ran.Lilian T. Hoffecker
We don't know if T. rex hunted alone or in packs, if it pursued live prey or merely scavenged.Discover Magazine
Spielberg's dinosaurs had teeth prominently and terrifyingly on constant display, much like a modern crocodile. [Auburn University professor Thomas] Cullen and his team, however, have shown instead that the T-Rex … had lips that covered their teeth much like a modern monitor lizard.John West
T. rexes were among the largest meat-eaters on Earth during their reign … 144 million years ago. They had to eat a lot, and often, to support their enormous bodies.John Johnson Jr.

Examples of T. rex in a Sentence

Recent Examples on the Web My generation, for the most part, can’t picture T. rex with any feathers at all. Rivka Galchen, The New Yorker, 6 Nov. 2023 Visitors can touch and hold real fossils, take a closer look at the nation’s T. rex, and see researchers at work in the FossiLab. Adele Chapin, Washington Post, 5 Oct. 2023 Read More: Could Spinosaurus Really Take On T. rex? Allison Futterman, Discover Magazine, 8 Sep. 2023 And here is the most surprising thing that all those ten-year-olds plus pretty much everyone else on the planet know about T. rex: the creature’s proper scientific name. Kathryn Schulz, The New Yorker, 14 Aug. 2023 The scientists also found teeth belonging to a T. rex predecessor and a crocodile, not to mention a bone that had once belonged to a tiny, chicken sized, meat-eating dinosaur called a Coelurosaur. Matt Hrodey, Discover Magazine, 25 July 2023 The appeal for private collectors is obvious: A T. rex makes for an awe-inspiring sculptural piece for that awkward-to-fill atrium. Lucy Alexander, Robb Report, 16 July 2023 Theropods are a class of large, three-toed, carnivorous dinosaurs that include the T. rex, though the bones discovered at Dinosaur Park predate the famous dinosaur. Christine Condon, Baltimore Sun, 13 July 2023 In fact, Wiseman mentions that the method has helped paleontologists figure out the shockingly slow running speeds of T. rexes. Sara Kiley Watson, Popular Science, 14 June 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'T. rex.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


New Latin, short for Tyrannosaurus rex

First Known Use

1915, in the meaning defined above

Time Traveler
The first known use of T. rex was in 1915

Dictionary Entries Near T. rex


T. rex


Cite this Entry

“T. rex.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2023.

Kids Definition

T. rex

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