gulfweed

noun

gulf·​weed ˈgəlf-ˌwēd How to pronounce gulfweed (audio)
: any of several sargassums
especially : a branching olive-brown seaweed (Sargassum natans) of tropical American seas with numerous berrylike air vesicles

Word History

Etymology

Gulf of Mexico

First Known Use

1674, in the meaning defined above

Time Traveler
The first known use of gulfweed was in 1674

Rhymes for gulfweed

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Browse Nearby Words

Gulf War syndrome
gulfweed
gulf-weed crab
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Cite this Entry

“Gulfweed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/gulfweed. Accessed 6 Jul. 2026.

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More from Merriam-Webster on gulfweed

Britannica.com: Encyclopedia article about gulfweed

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