seaweed

noun

sea·​weed ˈsē-ˌwēd How to pronounce seaweed (audio)
1
plural seaweeds : any of various aquatic and chiefly marine brown, red, or green algae (such as rockweed, gulfweed, and kelp) that often grow in masses, typically have leaflike blades (see blade entry 1 sense 2e), are usually anchored to a solid substrate (such as a rock) by holdfasts (see holdfast sense 2a), and include some (such as dulse, laver, and sea lettuce) that are used as food
… many seaweeds have floats called pneumatocysts, filled with oxygen or carbon dioxide.Michael Le Page
The word seaweed is broad and refers generally to marine macroalgae, which are algae living in salt or brackish water and visible to the eye.Elyse Inamine
2
: a mass or growth of seaweeds
… soft crabs were easily visible in the seaweed, because the water was crystal clear then.Keith Walters
3
: harvested seaweed or seaweed parts used especially as food, fertilizer, and in cosmetics
… sushi rolls wrapped in thin sheets of dried seaweedJane Snow

Examples of seaweed in a Sentence

Recent Examples on the Web Jack squatted down to August’s eye level (a go-to parenting move of Prince William and Kate Middleton), seemingly amusing the adorable tot with what appeared to be seaweed on his head under his hat! Janine Henni, Peoplemag, 3 May 2024 Gobler began incorporating seaweed into his labs about a decade before kelp. Julia Jacobo, ABC News, 2 May 2024 See all Example Sentences for seaweed 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'seaweed.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1577, in the meaning defined at sense 1a

Time Traveler
The first known use of seaweed was in 1577

Dictionary Entries Near seaweed

Cite this Entry

“Seaweed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/seaweed. Accessed 19 May. 2024.

Kids Definition

seaweed

noun
sea·​weed -ˌwēd How to pronounce seaweed (audio)
: a plant growing in the sea
especially : a marine alga (as a kelp)

More from Merriam-Webster on seaweed

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!