Definition of mosasaur
: any of a family (Mosasauridae) of very large extinct marine fish-eating lizards of the Upper Cretaceous with limbs modified into paddles that are related to the recent monitor lizards
Origin of mosasaur
New Latin Mosasaurus, from Latin Mosa the river Meuse + Greek sauros lizard
First Known Use: 1841
Learn More about mosasaur
Britannica.com: Encyclopedia article about "mosasaur"
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