mosasaur

American  

[moh-suh-sawr] / ˈmoʊ səˌsɔr /

noun

1. any of several extinct carnivorous marine lizards from the Cretaceous Period, having the limbs modified into broad, webbed paddles.

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mosasaur British  

/ ˌməʊsəˈsɔːrəs, ˈməʊsəˌsɔː /

noun

1. any of various extinct Cretaceous giant marine lizards of the genus Mosasaurus and related genera, typically having paddle-like limbs

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mosasaur Scientific  

/ mō′sə-sôr′ /

1. Any of various medium-sized to large extinct aquatic lizards of the family Mosasauridae of the Cretaceous Period, having modified limbs that served as paddles for swimming. Some species reached lengths of over 15 meters (50 feet).

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Etymology

Origin of mosasaur

< New Latin Mosasaurus (1823) genus name, equivalent to Latin Mosa the Meuse river (where a species was first discovered) + New Latin -saurus -saur

Example Sentences

"It highlights the need to revisit long-standing assumptions about mosasaur evolution and to modernize the tools we use to study these iconic marine reptiles."

From Science Daily • May 23, 2026

Other famous mosasaur fossils previously identified as T. proriger are now being reassigned to T. rex.

From Science Daily • May 23, 2026

Skeletal replicas of the terrifying mosasaur, a Komodo Dragon relative with a six-foot jaw; the saber-toothed salmon; and other extinct species greet visitors in the museum’s entrance hall.

From The Wall Street Journal • Apr. 2, 2025

The mosasaur was named for the place where it was found, Wakayama Prefecture.

From Science Daily • Dec. 12, 2023

And the mosasaurus—that was the biggest, meanest, toothiest, most unstoppable mosasaur there was.

From "Dactyl Hill Squad" by Daniel José Older