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dinosaur

[ dahy-nuh-sawr ]
/ ˈdaɪ nəˌsɔr /
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noun

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.
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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RELATED WORDS

antiquated, archaic, outmoded, out-of-date, obsolete, antique, bent, tired, superseded, dated, superannuated, out, outworn, fossilized, ancient, antediluvian, bygone, dead, discarded, dusty

Nearby words

  1. dinnertime,
  2. dinnerware,
  3. dino-,
  4. dinoceras,
  5. dinoflagellate,
  6. dinosaur national monument,
  7. dinosaurian,
  8. dinosaurs,
  9. dinothere,
  10. dinotherium

Origin of dinosaur

< New Latin Dinosaurus (1841), originally a genus name. See dino-, -saur
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for dinosaur

British Dictionary definitions for dinosaur

dinosaur

/ (ˈdaɪnəˌsɔː) /

noun

any extinct terrestrial reptile of the orders Saurischia and Ornithischia, many of which were of gigantic size and abundant in the Mesozoic eraSee also saurischian, ornithischian Compare pterosaur, plesiosaur
a person or thing that is considered to be out of date
Derived Formsdinosaurian, adjective

Word Origin for dinosaur

C19: from New Latin dinosaurus, from Greek deinos fearful + sauros lizard
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for dinosaur

dinosaur

n.

1841, coined in Modern Latin by Sir Richard Owen, from comb. form of Greek deinos "terrible" (see dire) + sauros "lizard" (see -saurus). Figurative sense of "person or institution not adapting to change" is from 1952.

Online Etymology Dictionary, © 2010 Douglas Harper
Science definitions for dinosaur

dinosaur

[ dī′nə-sôr′ ]

Any of various extinct reptiles of the orders Saurischia and Ornithischia that flourished during the Mesozoic Era. Dinosaurs were carnivorous or herbivorous, dwelled mostly on land, and varied from the size of a small dog to the largest land animals that ever lived. One group of dinosaurs evolved into birds. See more at ornithischian saurischian. See Note at bird.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.