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3 : one that is impractically large, out-of-date, or obsolete The factory is now a rusting dinosaur.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

Synonyms for dinosaur


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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 Robust ecosystems are less vulnerable to phytophthora, and the kauri forests of New Zealand’s north had been thriving since the time of the dinosaurs. Washington Post, "For New Zealand's Maoris, even touching this sacred tree is taboo. They let scientists climb to help save it.," 12 Jan. 2020 There’s a reason that Tyrannosaurus rex has earned its reputation as the king of dinosaurs. Kate Baggaley, Popular Science, "T. rex teens looked wildly different than the adults we’re familiar with," 3 Jan. 2020 Officials estimate about 48% of the iconic Gondwana reserves, which include rainforests that have existed since the time of the dinosaurs, have now burned. John Pickrell, Science | AAAS, "A fires rage across Australia, fears grow for rare species," 17 Dec. 2019 Just how big of a scourge were lice during the days of the dinosaurs? Brian Handwerk, Smithsonian, "Lice-Filled Dinosaur Feathers Found Trapped in 100-Million-Year-Old Amber," 10 Dec. 2019 Iridium was also found at the site of the impact crater associated with the extinction of the dinosaurs. Ashley Strickland, CNN, "Something crashed into Earth and helped wipe out mammoths and other animals 13,000 years ago, study says," 29 Oct. 2019 Paleontologists in Denver have uncovered a treasure trove of fossils that give a thrilling new insight into the rise of mammals after the extinction of the dinosaurs. Cathleen O'grady, Ars Technica, "Fossil bonanza paints detailed picture of mammals after dinosaur extinction," 25 Oct. 2019 That seemed to draw people out of the woodwork, and Morris said the vast majority of visitors are there for one last glimpse before Bedrock goes the way of the dinosaurs. Scott Craven, azcentral, "There's still time to see Bedrock City before it becomes Raptor Ranch," 18 Oct. 2019 Sturgeons may have survived the demise of the dinosaurs, but chances are high that they will be wiped out within years. Denise Hruby, Los Angeles Times, "Craving for caviar is driving the Danube River’s sturgeon to extinction," 22 Aug. 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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Time Traveler for dinosaur

Time Traveler

The first known use of dinosaur was in 1841

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Statistics for dinosaur

Last Updated

17 Jan 2020

Cite this Entry

“Dinosaur.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/dinosaur. Accessed 26 January 2020.

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More Definitions for dinosaur


How to pronounce dinosaur (audio)

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

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