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Mosasaurus

noun
Mo·​sa·​sau·​rus

Definition of Mosasaurus 

: a genus (the type of the family Mosasauridae) of large extinct aquatic Cretaceous fish-eating lizards related to the recent monitors but having the limbs modified into swimming paddles

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History and Etymology for Mosasaurus

New Latin, from Latin Mosa the river Meuse (near which the first known species was discovered) + New Latin -saurus

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