[moh-suh-sawr] 
| any of several extinct carnivorous marine lizards from the Cretaceous Period, having the limbs modified into broad, webbed paddles. |
| mo·sa·saur (mō'sə-sôr') n. Any of various very large extinct aquatic lizards of the genus Mosasaurus, having modified limbs that served as paddles for swimming. These lizards, thought to have been viviparous and carnivorous, may be early ancestors of the modern monitor lizard. [New Latin Mosasaurus, genus name : Latin Mosa, the Meuse River (where fossils of the genus were first discovered) + Greek sauros, lizard.] |
| mosasaur (mō'sə-sôr') Pronunciation Key
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. |
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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səˌsɔr