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3 : one that is impractically large, out-of-date, or obsolete The factory is now a rusting dinosaur.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

Twenty-five years ago, the dinosaurs — wondrous and horrifying creations at once — stood for the magical but fearsome power of genetic engineering. Washington Post, "In ‘Jurassic World,’ a dino-sized animal-rights parable," 18 June 2018 In this biography of these creatures, paleontologist Brusatte weaves together the origins of dinosaurs, their rise to global dominance and their dramatic demise. Andrea Gawrylewski, Scientific American, "The Ultimate Dinosaur Biography, A Cosmological Caper and Other New Science Books," 1 Apr. 2018 At Henn-Na, dinosaurs, cyborgs, and other multi-lingual A.I. creatures check you in and drop off your bags, while all food comes from vending machines. Erin Florio, Condé Nast Traveler, "This Floating Bubble May Be Japan’s Wackiest Hotel Yet," 29 Mar. 2018 Scientists know that birds evolved from dinosaurs, and Archaeopteryx is part of that evolutionary path. Ashley Strickland, CNN, "This 'enigmatic' feathered dinosaur didn't fly like modern birds," 13 Mar. 2018 In this case, dinosaur-era piranhas that had lain dormant for many, many centuries had come back to life to terrorize a lakeside community. Lindsey Lanquist, SELF, "I Tracked My Heart Rate While Watching the 10 'Scariest' Movies on Netflix," 14 June 2018 Also enjoy popcorn samples from AMC CityPlace 20, a dinosaur sculpture and live music 7:30 to 10:30 p.m. Free. Jennifer Jhon, South Florida Parenting, "What to do with the kids this weekend: cartoons, Wizard of Oz," 6 June 2018 To its credit, Fallen Kingdom doubles down on making the audience emotionally invest in the dinosaurs as actual animals. Bryan Bishop, The Verge, "Jurassic World: Fallen Kingdom is a stunning disappointment," 22 June 2018 It's done especially well internationally, which has made up 69 percent of the dinosaur sequel's global footprint. Jake Coyle, Houston Chronicle, "'Ant-Man and the Wasp' buzzes to $76 million debut," 9 July 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

7 Nov 2018

Look-up Popularity

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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