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.
Land slugs can carry rat lungworm, a parasite that can cause serious neurological disease in humans, and many sea slugs contain defensive toxins acquired from their prey. — Encyclopedia Britannica, 10 July 2026 The tide pools around Haystack and elsewhere along Cannon Beach are extraordinary, with colorful sea stars, anemones, crabs, snails, coral, sponges, and sea slugs. — Kara Williams, USA Today, 25 Apr. 2026 Researchers with the Harte Research Institute say blue dragons, tiny blue sea slugs with a painful sting, are washing up again along Texas beaches as spring winds push offshore marine life onto shore. — Dante Motley, Austin American Statesman, 11 Mar. 2026 Along with tiny sea slugs, elegant birds and strange, fuzzy flowers, the marine oddity is just one of 72 species of plants, animals and fungi discovered by researchers at the California Academy of Sciences last year. — Luis Melecio-Zambrano, Mercury News, 18 Jan. 2026 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

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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 12 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

Last Updated: - Updated example sentences
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