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 a person or thing that is considered to be out of date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

Earlier, a number of specimens, including parts of the early dinosaur Thecodontosaurus, were destroyed in Bristol after an Axis raid in 1940.

From Science Daily ● Aug. 7, 2026

The Cretaceous Period was the final major chapter of the dinosaur age.

From Science Daily ● Aug. 5, 2026

The mixture of satisfaction, excitement and sheer bewilderment that Neill wore in the first dinosaur scene in “Jurassic Park” was so effective that it made viewers feel like they, too, were witnessing something beyond imagination.

From Salon ● Jul. 17, 2026

It’s an auction record for a fossilized dinosaur skeleton, beating a 150-million-year-old Stegosaurus that sold for $44.6 million two years ago.

From The Wall Street Journal ● Jul. 14, 2026

And like the purple dinosaur, Benji was kind of awkward.

From "Millionaires for the Month" by Stacey McAnulty

A 31-foot predator that once hunted dinosaurs across what is now the eastern United States has been reconstructed in scientifically accurate, life-size form for the first time.

From Science Daily ● Aug. 5, 2026

The CSA warned the incident shows that AI "agents... find a way" - a reference to the film Jurassic Park, where dinosaurs escape their enclosures.

From BBC ● Jul. 28, 2026

This prehistoric creature has survived ice ages, the asteroid impact that killed the dinosaurs, and continental drift.

From BBC ● Jul. 27, 2026

The dinosaurs, Uberabatitan from Brazil and Neuquensaurus from Argentina, were modest in size compared with the largest sauropods.

From Science Daily ● Jul. 20, 2026

There were T-shirts with dinosaurs and all kinds of mugs.

From "It All Comes Down to This" by Karen English

Related Words

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• out-of-date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