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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Mathematical models showed that the size of tyrannosaurids such as T. rex rapidly increased as global temperatures dropped. Ashley Strickland, CNN Money, 11 May 2025 Yes, the remnants of the prehistoric predator are being used to create synthetic T. rex leather, which can be turned into accessories including purses. Mike Snider, USA Today, 11 May 2025 The authors of that study say those findings support North American ancestry for T. rex. Paul Smaglik, Discover Magazine, 8 May 2025 In a post-Cretaceous world, birds have likely never experienced sufficient evolutionary pressure to be as tall or as massive as T. rex. Riley Black, Smithsonian Magazine, 6 May 2025 See All Example Sentences for T. rex

Word History

Etymology

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

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Cite this Entry

“T. rex.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/T.%20rex. Accessed 21 May. 2025.

Kids Definition

T. rex

noun
Last Updated: - Updated example sentences
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