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[moh-suh-sawr] /ˈmoʊ səˌsɔr/
any of several extinct carnivorous marine lizards from the Cretaceous Period, having the limbs modified into broad, webbed paddles.
< New Latin Mosasaurus (1823) genus name, equivalent to Latin Mosa the Meuse river (where a species was first discovered) + New Latin -saurus -saur Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for mosasaur
  • Instead a totally new group enters the sea-monster guild, the long-bodied sea lizards of the mosasaur family.
  • In reptiles, mosasaur jaws and teeth and their ecology are introduced for instance.
British Dictionary definitions for mosasaur


noun (pl) -saurs, -sauri (-ˈsɔːraɪ)
any of various extinct Cretaceous giant marine lizards of the genus Mosasaurus and related genera, typically having paddle-like limbs
Word Origin
C18: from Latin Mosa the river Meuse (near which remains were first found) + -saur
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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mosasaur in Science
Any of various medium-sized to large extinct aquatic lizards of the genus Mosasaurus of the Cretaceous Period, having modified limbs that served as paddles for swimming. Mosasaurs were related to the modern monitor lizard, with which they share a similar skull structure.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Article for mosasaur

extinct aquatic lizards that attained a high degree of adaptation to the marine environment and were distributed worldwide during the Cretaceous Period (144 million to 65 million years ago). The mosasaurs competed with other marine reptiles-the plesiosaurs and ichthyosaurs-for food, which consisted largely of ammonoids, fish, and cuttlefish. Many mosasaurs of the Late Cretaceous were large, exceeding 9 metres (30 feet) in length, but the most common forms were no larger than modern porpoises.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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