dinosaur

American  

[dahy-nuh-sawr] / ˈdaɪ nəˌsɔr /

noun

• dinosaurs
  plural

1. 

   any chiefly terrestrial, herbivorous or carnivorous reptile of the extinct orders Saurischia and Ornithischia, from the Mesozoic Era, certain species of which are the largest known land animals.

2. something that is unwieldy in size, anachronistically outmoded, or unable to adapt to change.

   The old steel mill was a dinosaur that cost the company millions to operate.

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dinosaur British  

/ ˈdaɪnəˌsɔː /

noun

1. any extinct terrestrial reptile of the orders Saurischia and Ornithischia, many of which were of gigantic size and abundant in the Mesozoic era See also saurischian ornithischian Compare pterosaur plesiosaur

2. a person or thing that is considered to be out of date

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Other Word Forms

Derived Forms

• dinosaurian
  adjective

Inflected Forms

Nouns

• dinosaurs
  plural

Etymology

Origin of dinosaur

< New Latin Dinosaurus (1841), originally a genus name. See dino-, -saur

Explanation

If you've ever seen Jurassic Park, you know that dinosaurs were large reptilian creatures that walked the earth during the Mesozoic era that ran from 245 million to 68 million years ago and included the Triassic, Jurassic, and Cretaceous periods. The ancient Greeks had no knowledge of dinosaurs that we know of, but they unknowingly contributed to the word dinosaur. It was cobbled together in 1841 by British scientist Sir Richard Own, using the words deinos, meaning "terrible" and sauros meaning "lizard." All are gone—at least in their original form, although it is thought they simply evolved into other, present-day animals. The word dinosaur is often used for someone who is old-fashioned or unable to adapt to modern times.

Example Sentences

See Examples For:

dinosaur dinosaurs

Together, these fossils suggest that the ancient coastal environments of the region supported complex and highly diverse dinosaur ecosystems.

From Science Daily ● Sep. 19, 2026

The area surrounding the fossil site has produced remains from numerous dinosaur groups, including sauropods, theropods, stegosaurs, and ornithopods.

From Science Daily ● Sep. 19, 2026

By examining that feather, scientists say they may have uncovered an important clue to why birds became the only dinosaur lineage to survive the mass extinction at the end of the Cretaceous Period.

From Science Daily ● Sep. 11, 2026

It also preserves evidence of an ancient food web, revealing what a large dinosaur consumed shortly before the end of the dinosaur era.

From Science Daily ● Sep. 11, 2026

Over the next several years the two men between them increased the number of known dinosaur species in America from 9 to almost 150.

From "A Short History of Nearly Everything" by Bill Bryson

Remarkably, evidence of that ancient meal survived in fossilized feces, preserving what researchers describe as the finest feather specimen yet discovered from the age of dinosaurs.

From Science Daily ● Sep. 11, 2026

"Our local dinosaurs are like missing jigsaw pieces that help establish evolutionary connections, particularly around the Jurassic and Cretaceous period transition, approximately 140 million years ago."

From Barron's ● Sep. 3, 2026

He has described watching his children donning Specs to run around playing laser tag, learn about dinosaurs and build with virtual Legos.

From The Wall Street Journal ● Sep. 2, 2026

Phil Tippett, the visual effects artist who crafted aliens in “Star Wars” and dinosaurs in “Jurassic Park,” is shutting down his Berkeley-based studios after more than 40 years of business.

From Los Angeles Times ● Aug. 31, 2026

At the time the conventional wisdom about the dinosaur extinction was the same as it had been in Charles Lyell’s day a century earlier–namely that the dinosaurs had died out over millions of years.

From "A Short History of Nearly Everything" by Bill Bryson

Related Words

• antiquated
• archaic
• out-of-date
• outmoded