T. rex
Americannoun
Usage
What is a T. rex? T. rex is short for Tyrannosaurus rex, a giant, meat-eating dinosaur that walked on two legs and had a long tail and a big head with sharp teeth (and, yes, two little arms).The name Tyrannosaurus rex comes from the Greek words tyranno (“tyrant”) and saurus (“lizard”) and the Latin word rex (“king”). So, Tyrannosaurus rex means something like “king of the tyrant lizards.” It is commonly called T. rex for short.The name is fitting: Tyrannosaurus rex is one of the largest land predators that has ever lived. It was the largest of the tyrannosaurs, reaching a length of 47 feet (14.3 m) or more.People often list the T. rex as their favorite dinosaur, and its popularity has grown through many pop culture depictions, such as its appearances in the Jurassic Park series of movies and books. However, to be scientifically precise about it, the T. rex lived during the Late Cretaceous period, about 90–65 million years ago, around the end of the age of dinosaurs.
Etymology
Origin of T. rex
First recorded in 1980–85; abbreviation of Tyrannosaurus rex ( def. )
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
A tridimensional T. rex protrudes from Iñaki Godoy’s head while he holds a small plush toy of Monkey D. Luffy, the character who changed his life forever.
From Los Angeles Times • Mar. 10, 2026
The study, published in the journal PeerJ, represents the most detailed reconstruction of the life history of T. rex so far.
From Science Daily • Mar. 5, 2026
The findings also hint that some fossils previously classified as T. rex could actually belong to different species or represent other biological differences.
From Science Daily • Mar. 5, 2026
Although Tyrannosaurus rex is the best known species in this group of dinosaurs, scientists continue to debate whether some fossils assigned to T. rex actually belong to closely related species.
From Science Daily • Mar. 5, 2026
That foliage could easily hide a T. rex.
From "The Last Cuentista" by Donna Barba Higuera
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
