sea·​weed | \ ˈsē-ˌwēd How to pronounce seaweed (audio) \

Definition of seaweed

1 : a mass or growth of marine plants
2 : a plant growing in the sea especially : a marine alga (such as a kelp)

Examples of seaweed in a Sentence

Recent Examples on the Web Wild Zala would roll in seaweed or a nicely aged seagull carcass. James Rainey, Los Angeles Times, 27 Aug. 2021 Plastic in the ocean breaks down into small particles that are caught in seaweed and ingested by marine creatures. Judith Magyar, Forbes, 24 May 2021 Swimmers were complaining of rashes, the ocean had grown thick with seaweed, and thousands of dead fish had washed ashore, along with eels, rays, turtles, dolphins, and even whales. Ian Urbina, The New Yorker, 1 Mar. 2021 People who favor more shoreline access say that’s not a clear enough line for people to actually be able to carry out their constitutional rights, which include in Rhode Island the right to pass along the shore and collect seaweed., 26 Aug. 2021 Use things like compost tea, seaweed/sea kelp tea or bone meal to increase the vitality of your plants. Claire Reid, Los Angeles Times, 10 Aug. 2021 Without any equipment, these women dive down 15 meters to collect shellfish and seaweed by hand, so that also inspired me. Alex Kessler, Vogue, 27 July 2021 For spider mites, spray garlic pepper tea or any spray that contains liquid seaweed. Howard Garrett, Dallas News, 28 June 2021 Those are real, used in Xiapu’s thriving aquaculture industry for drying seaweed. New York Times, 28 June 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'seaweed.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of seaweed

1577, in the meaning defined at sense 1

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Time Traveler for seaweed

Time Traveler

The first known use of seaweed was in 1577

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Dictionary Entries Near seaweed



seaweed crab

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Statistics for seaweed

Last Updated

9 Sep 2021

Cite this Entry

“Seaweed.” Dictionary, Merriam-Webster, Accessed 16 Sep. 2021.

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More Definitions for seaweed



English Language Learners Definition of seaweed

: a type of plant that grows in the sea


sea·​weed | \ ˈsē-ˌwēd How to pronounce seaweed (audio) \

Kids Definition of seaweed

: an alga (as a kelp) that grows in the sea

More from Merriam-Webster on seaweed

Nglish: Translation of seaweed for Spanish Speakers

Britannica English: Translation of seaweed for Arabic Speakers Encyclopedia article about seaweed


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