di·no·saur | \ ˈdī-nə-ˌsȯr \

Definition of dinosaur 

1 : any of a group (Dinosauria) of extinct often very large chiefly terrestrial carnivorous or herbivorous reptiles of the Mesozoic era

2 : any of various large extinct reptiles (such as ichthyosaurs) other than the true dinosaurs

3 : one that is impractically large, out-of-date, or obsolete The factory is now a rusting dinosaur.

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Other words from dinosaur

dinosaurian \ˌdī-nə-ˈsȯr-ē-ən \ adjective
dinosauric \-ˈsȯr-ik \ adjective

Examples of dinosaur in a Sentence

The old factory is now a rusting dinosaur. The character she plays is a dinosaur—a former beauty queen who is living in the past.

Recent Examples on the Web

Wide shots show her clicking and clacking as she's chased by dinosaurs in a jungle. April Wolfe, chicagotribune.com, "The tortured history of action-film heroines and their high heels ('Jurassic World,' anyone?)," 22 June 2018 And anyway, how much could Meredith even expect to get for these dinosaurs? Joe Pompeo, The Hive, "80 Potential Buyers, Titles for as Much as $200 Million: The Time Inc. Auction Sparks Surprising Hope for the Magazine Business," 23 May 2018 The late Triassic period roughly 210 million years ago was a critical time for the evolution of dinosaurs, researchers said. Brett Molina, USA TODAY, "Fossil of first giant dinosaur, dubbed Ingentia prima, found in Argentina," 11 July 2018 Bad news for fans of Costco’s food court: the Polish hot dog is going the way of the dinosaur. Meghan Overdeep, Southern Living, "Costco Is Removing This Beloved Mainstay from Its Food Court Menus," 10 July 2018 Portrayals of dinosaurs with lizard-like tongues hearken to early interpretations of the beasts as oversized lizards. Mindy Weisberger, Scientific American, "T. Rex Couldn’t Stick Out Its Tongue," 24 June 2018 And of course many of the dinosaurs are glorious species. Kathryn Shattuck, New York Times, "Jeff Goldblum, Back in ‘Jurassic World’ and Making a Small Role Big," 15 June 2018 The film revealed scientists’ revised view of dinosaurs as active, intelligent animals to the public. Eva Botkin-kowacki, The Christian Science Monitor, "Rise of the 'Jurassic Park' generation," 11 June 2018 In the case of the dinosaurs, the catastrophe was an asteroid impact. The Economist, "The Cambrian explosion was caused by a lack of oxygen, not an abundance," 7 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'dinosaur.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of dinosaur

1841, in the meaning defined at sense 1

History and Etymology for dinosaur

New Latin Dinosaurus, genus name, from Greek deinos terrifying + sauros lizard — more at dire

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Statistics for dinosaur

Last Updated

12 Sep 2018

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Time Traveler for dinosaur

The first known use of dinosaur was in 1841

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English Language Learners Definition of dinosaur

: one of many reptiles that lived on Earth millions of years ago

: someone or something that is no longer useful or current : an obsolete or out-of-date person or thing


di·no·saur | \ ˈdī-nə-ˌsȯr \

Kids Definition of dinosaur

: any of a group of extinct often very large mostly land-dwelling reptiles that lived millions of years ago

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Comments on dinosaur

What made you want to look up dinosaur? Please tell us where you read or heard it (including the quote, if possible).


to deposit or conceal in a hiding place

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