T. rex

noun

ˈtē-ˈreks 

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

Sue is the largest and most complete T. rex specimen paleontologists have ever found. —Laura Baisas, Popular Science, 12 Mar. 2026

Shumway explains that the T. rex, being a Cretaceous species, is actually closer in time to humans than to Jurassic dinosaurs like the stegosaurus. —The Washington Post, San Diego Union-Tribune, 10 Mar. 2026

Paleontologists have announced the discovery of a new species of Spinosaurus — the meat-eating dinosaur that may have rivaled T. rex in size. —Andrea Margolis, FOXNews.com, 1 Mar. 2026

Long overshadowed in the public imagination by T. rex, Spinosaurus is now having its time in the spotlight. —Reuters, NBC news, 20 Feb. 2026

Word History

Etymology

New Latin, short for Tyrannosaurus rex

First Known Use

1915, in the meaning defined above

Rhymes for T. rex

• becks
• checks
• czechs
• decks
• dex
• ex
• flecks
• flex
• hex
• lex
• necks
• pecks

Kids Definition

T. rex

noun

ˈtē-ˈreks 

: tyrannosaur