di·​no·​saur | \ ˈdī-nə-ˌsȯr How to pronounce dinosaur (audio) \

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3 : one that is impractically large, out-of-date, or obsolete The factory is now a rusting dinosaur.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 How to pronounce dinosaurian (audio) \ adjective
dinosauric \ -​ˈsȯr-​ik How to pronounce dinosauric (audio) \ adjective

Synonyms for dinosaur


has-been, relic

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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

The costume based on a video game has been super popular among U.S. residents, with costumes inspired by Spider-Man, unicorns, dinosaurs, witches, and Harley Quinn following close behind. Lauren Rearick, Teen Vogue, "Google Released the Most-Googled Halloween Costumes," 22 Oct. 2018 If mythical creatures aren't your thing, the sprinkler also comes in five other styles: a dinosaur, pink and blue elephant, monster, and ape. Kelly O'sullivan, Country Living, "Every Summer BBQ Needs This 7-Foot-Tall Unicorn Sprinkler," 15 Mar. 2018 Soon the boys are hiding from dinosaurs and shooting sniper rifles. Sam Dangremond, Town & Country, "Maria Shriver Just Shared Her Son Patrick Schwarzenegger's New Look From a Brooklyn Movie Set," 18 July 2018 However, it may be composed of skeletons from two different dinosaurs, according to Science. Sarah Gray, Fortune, "Dinosaur Skeleton Sells for Over $2 Million at Auction in Paris," 3 Feb. 2018 Arizona Museum of Natural History Explore the history of the Southwest, from dinosaurs to territorial explorers, at the Arizona Museum of Natural History. Sonja Haller, azcentral, "Ultimate Arizona bucket list: 25 things to do in Mesa," 18 Feb. 2015 The question of sperm in precum usually comes up in reference to the pull-out method, also known as the withdrawal method (and coitus interruptus—sounds like a dinosaur, but OK). Kasandra Brabaw, SELF, "Can You Get Pregnant From Precum?," 7 Mar. 2019 The conglomerate, usually considered a corporate dinosaur, is finding a surprising new lease of life in the airline industry. Jon Sindreu, WSJ, "Why Airlines Are Rebuilding the Conglomerate," 5 Mar. 2019 South America and Africa became two separate entities, and took with them related species of dinosaurs that would drift apart genetically. John Wenz, Popular Mechanics, "Meet the New Titanosaur, a Giant That Fills in Dinosaur Fossil Gaps," 13 Feb. 2019

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

11 Apr 2019

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Time Traveler for dinosaur

The first known use of dinosaur was in 1841

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More Definitions for dinosaur



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 How to pronounce dinosaur (audio) \

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 affect and impair by alcohol or a drug

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