sea monster

noun

plural sea monsters

: a mythical creature of usually immense size that lives underwater and is traditionally regarded as a threat to ships and mariners

All readers of Yeats will need this book; when they open it they will feel a surprise like that experienced by St. Brendan the Navigator and his crew when they disembarked upon an island that turned out to be the back of a dormant sea monster.

—Seamus Heaney

Examples of sea monster in a Sentence

Recent Examples on the Web

Watch The Incredibles films on Disney+ Luca Luca (Jacob Tremblay) and Alberto (Jack Dylan Grazer) are sea monsters who feel stifled in the water. —Sydni Ellis, PEOPLE, 7 Sep. 2025

Scenic artists Abby Palen and Rachel Hartmann add delightful touches, including a wonderfully weird sea monster. —Sheila Regan, Twin Cities, 22 Aug. 2025

China’s sea monster Another nation picking up the Ekranoplan baton is China. —Christopher McFadden, Interesting Engineering, 4 Aug. 2025

But none of those come close to the double trouble mythical sea monsters that attack the ironclad in the Sea of Monsters at a crucial moment in both Clarisse and Percy's quests. —EW.com, 22 July 2025

Word History

First Known Use

1568, in the meaning defined above