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

Because the mosasaur tooth, the T. rex tooth, and the crocodylian jawbone all date to roughly the same time, about 66 million years ago, the scientists could directly compare their chemistry.

From Science Daily • Dec. 15, 2025

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

It was near there that a new kind of mosasaur, a type of giant sea creature, was discovered, scientists announced last week.

From New York Times • Nov. 5, 2023

Like the mosasaur tooth, it had somehow ended up miles inland from the sea of its origin.

From The New Yorker • Mar. 29, 2019

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

From "Dactyl Hill Squad" by Daniel José Older