T. rex

[tee reks]

noun

1. tyrannosaur.

Word History and Origins

Origin of T. rex¹

First recorded in 1980–85; abbreviation of Tyrannosaurus rex ( def. )

When To Use

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.