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 a person or thing that is considered to be out of date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

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Etymology

Origin of dinosaur

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

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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

The dinosaur, named Invictibellatrix amberina, is described in a new paper in the journal Royal Society Open Science and belongs to a group of agile, two-legged carnivores called megaraptorans.

From BBC ● Oct. 14, 2026

A new species of dinosaur - a long-clawed predator the size of a large tiger - has been identified from a fossil found on the Isle of Wight more than 100 years ago.

From BBC ● Oct. 14, 2026

Since then, the African dinosaur map has expanded, with rich fossil beds in South Africa, Lesotho, Tanzania, Egypt, Niger, Malawi, Madagascar and Morocco.

From Science Daily ● Oct. 13, 2026

A fractured rib from Scotty, the largest Tyrannosaurus rex skeleton ever discovered, is giving researchers a rare look at dinosaur biology from 66 million years ago.

From Science Daily ● Sep. 24, 2026

I turn to see what she sees—a serpent the size of a dinosaur.

From "Kwame Crashes the Underworld" by Craig Kofi Farmer

They compared the fossil with skulls and brain cases from tyrannosaurs, spinosaurs, raptors and other two-legged meat-eating dinosaurs.

From BBC ● Oct. 14, 2026

The team then compared its anatomy with fossils from several other groups of meat-eating dinosaurs, including tyrannosaurs, spinosaurs, raptors, and other predators that walked on two legs.

From Science Daily ● Oct. 14, 2026

It would have eaten small dinosaurs, lizards and mammals – occupying a similar role in the food chain to the hyena today.

From BBC ● Oct. 14, 2026

Megaraptors are regarded as the most mysterious of the large, meat-eating dinosaurs, as few megaraptor fossils have been found.

From BBC ● Oct. 14, 2026

I thought about that, considered that dinosaurs, real dinosaurs, had walked near where I now sat in a Chinese restaurant drinking a Shirley Temple, tens of millions of years later.

From "The Thing About Jellyfish" by Ali Benjamin

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Related Words

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• out-of-date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

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