Definition of dinosaur in English:

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Pronunciation: /ˈdīnəˌsôr/


Image of dinosaur
1A fossil reptile of the Mesozoic era, often reaching an enormous size.

The dinosaurs are placed, according to their hip structure, in two distantly related orders (see ornithischian and saurischian). Some of them may have been warm-blooded, and their closest living relatives are the birds. Dinosaurs were all extinct by the end of the Cretaceous period (65 million years ago), a popular theory being that the extinctions were the result of the impact of a large meteorite.

Example sentences
  • These great birds were the last successors of the mighty theropod dinosaurs of the Mesozoic.
  • We are so used to the enormous size of dinosaurs that we almost forget to think about how they grew to be so large.
  • They do still have two skeletons of Tarbosaurus, a theropod dinosaur related to Tyrannosaurus rex.
2A person or thing that is outdated or has become obsolete because of failure to adapt to changing circumstances.
Example sentences
  • I still get invites but I feel like a dinosaur and a bit of a has-been now.
  • He is like a Tyrannosaurus Rex, leading a herd of corporate dinosaurs over the cliff and bellowing as he goes.
  • She said: "I suppose at 30 I'm considered a bit of a dinosaur in the industry."



Pronunciation: /ˌdīnəˈsôrēən/
adjective& noun
Example sentences
  • Thirty years later, the cave city of Matera still stands on the ravine over the River Gravina, a dinosaurian pile the colour of the sandy earth.
  • Amongst these dinosaurian beasts, horses were keeping cool in the hazy, humid heat, by standing knee deep in the shallow water.
  • This, the last period of dinosaurian evolution, was also the period of their greatest diversity, although only a fraction of the types (mainly latest Cretaceous Western North American and Asian forms) are known.


Mid 19th century: from modern Latin dinosaurus, from Greek deinos 'terrible' + sauros 'lizard'.

  • The word dinosaur was coined in 1841, from Greek words meaning ‘terrible lizard’, the -saurus, also found in saurian (early 19th century) ‘lizard-like’. People or things that have not adapted to changing times have been condemned as dinosaurs since the 1950s.

For editors and proofreaders

Syllabification: di·no·saur

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