Definition of mosasaur in English:

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Pronunciation: /ˈməʊzəsɔː/


A large fossil marine reptile of the late Cretaceous period, with large toothed jaws, paddle-like limbs, and a long flattened tail, related to the monitor lizards.
  • Family Mosasauridae, suborder Lacertilia: several genera, including Mosasaurus.
Example sentences
  • The remains include the bones of dinosaurs, birds, and large marine reptiles such as mosasaurs and elasmosaurs, as well as fossilized sponges, mollusks, pine cones, and diverse fish teeth.
  • The dinosaurs were only one of the groups that became extinct at the end of the Cretaceous; also hard-hit were the unicellular Foraminifera, the ammonites, and marine reptiles such as the mosasaurs and plesiosaurs.
  • Today paleontologists know the Badlands are full of bones of mosasaurs (giant marine reptiles that plied an inland sea there during the Cretaceous period) and pterosaurs (giant flying reptiles).


Mid 19th century: from modern Latin Mosasaurus, from Latin Mosa, 'Meuse' (the river near which it was first discovered) + Greek sauros 'lizard'.

For editors and proofreaders

Line breaks: mosa|saur

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