Definition of dinosaur in English:


Line breaks: dino|saur
Pronunciation: /ˈdʌɪnəsɔː


  • 1A fossil reptile of the Mesozoic era, often reaching an enormous size.
    More 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.
  • 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), possibly as a result of a catastrophic asteroid impact in the Gulf of Mexico

  • 2A person or thing that is outdated or has become obsolete because of failure to adapt to changing circumstances.
    More 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: /-ˈsɔːrɪən/
adjective & noun
More 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'.

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Pronunciation: ˌastrə(ʊ)ˈgeɪʃ(ə)n
(in science fiction) navigation in outer space