dinosaurs

Cultural  

1. Reptiles, now extinct, that were the dominant life form on Earth for many millions of years. The name dinosaur comes from the Greek words for “monstrous lizard.” Dinosaurs became extinct suddenly, about sixty-five million years ago. Scientists now believe that their extinction was caused by the impact of a large asteroid on the Earth.

---

Discover More

Some dinosaurs were very large and had small brains — factors that may in part have led to their extinction. The term is often used to refer to something or someone that is antiquated and unable to adapt to change: “The old cavalry generals couldn't adjust to the use of tanks — they became dinosaurs.”

Some scientists believe that modern birds are the descendants of dinosaurs.

Commonly known dinosaurs include Tyrannosaurus rex, Brontosaurus, Stegosaurus, and Triceratops.

Example Sentences

"So Megalosaurus, Cetiosaurus and other dinosaurs would have been living on these little islands."

From BBC • Jun. 10, 2026

Fast facts: A sci-fi thrill ride starring Anne Hathaway and Ewan McGregor as parents who have to fight for their lives when their whole street is mysteriously transported to a world with dinosaurs.

From The Wall Street Journal • Jun. 6, 2026

Like other unenlagiids, Kank australis possessed the enlarged claw on its second toe that is often associated with raptor dinosaurs.

From Science Daily • May 29, 2026

With the longtime teacher’s approval, Cervantes and a friend kept a pair of dinosaurs; one was named Tom, and the other Jerry, inspired by the show Cervantes loved watching with his dad growing up.

From Los Angeles Times • May 29, 2026

We talk about other things, like the first-grade field trip we made to the Smithsonian Museum, when I got so scared of the life-size dinosaurs that I cried in the bathroom.

From "A Place at the Table" by Saadia Faruqi and Laura Shovan