dinosaurs

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.

Notes

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

The pterosaurs are extinct flying reptiles that lived alongside their close relatives, the dinosaurs.

From Science Daily

The earth the dinosaurs once trod is now a massive expanse of solid rock.

From Los Angeles Times

Navaornis lived approximately 80 million years ago in what is now Brazil, before the mass extinction event that killed all non-avian dinosaurs.

From BBC

National letters of intent have gone the way of typewriters, rotary telephones and dinosaurs.

From Los Angeles Times

He loved dinosaurs and Pokémon, but most of all he loved penguins and dreamed of adopting one.

From BBC