dinosaur

[ dahy-nuh-sawr ]
See synonyms for dinosaur on Thesaurus.com
noun
  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.

Origin of dinosaur

1
<New Latin Dinosaurus (1841), originally a genus name. See dino-, -saur

Words Nearby dinosaur

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How to use dinosaur in a sentence

British Dictionary definitions for dinosaur

dinosaur

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 a person or thing that is considered to be out of date

Origin of dinosaur

1
C19: from New Latin dinosaurus, from Greek deinos fearful + sauros lizard

Derived forms of dinosaur

  • dinosaurian, adjective

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

Scientific definitions for dinosaur

dinosaur

[ nə-sôr′ ]


  1. 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.