sea slug

noun

1
: sea cucumber
2
: a naked marine gastropod
specifically : nudibranch

Examples of sea slug in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
She is fascinated by a tiny creature known as a nudibranch, more popularly called sea slugs. — Ernie Cowan, San Diego Union-Tribune, 23 Nov. 2025 During the nighttime low-tide surveys, researchers scoured the various pools and found a brightly colored sea slug, the study said. — Aspen Pflughoeft, Miami Herald, 27 Oct. 2025 The divers found a swath of ocean populated by weird and wild creatures, from delicate corals and shimmering worms to spiky sea slugs and hairy crabs. — Laura Paddison, CNN Money, 19 Dec. 2025 The sea slug, Kukushkin said, can complicate neuroscience’s behavioral bias. — Claire L. Evans, Quanta Magazine, 30 July 2025 See All Example Sentences for sea slug

Word History

First Known Use

1779, in the meaning defined at sense 1

Time Traveler
The first known use of sea slug was in 1779

Rhymes for sea slug

See All Rhymes for sea slug

Browse Nearby Words

sea slope
sea slug
sea smoke
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Cite this Entry

“Sea slug.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sea%20slug. Accessed 8 Jul. 2026.

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Kids Definition

sea slug

noun
1
: sea cucumber
2
: any of several marine mollusks that have no shell

More from Merriam-Webster on sea slug

Britannica.com: Encyclopedia article about sea slug

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