sar·​gas·​sum | \ sär-ˈga-səm How to pronounce sargassum (audio) \

Definition of sargassum

: any of a genus (Sargassum) of brown algae that have a branching thallus with lateral outgrowths differentiated as leafy segments, air bladders, or spore-bearing structures : gulfweed

Examples of sargassum in a Sentence

Recent Examples on the Web

Nutrient pollution could bolster competing species, like stringy sargassum, a nonnative macroalgae that Berry said has been found where South Puget Sound bull kelp beds once flourished. Evan Bush, The Seattle Times, "Another vital forest at risk: Scientists fear warming water could be killing off Puget Sound’s kelp beds," 15 Sep. 2019 Areas that take hours to clean end up are covered in sargassum only hours later. Andrea Navarro,, "Cancun has a nasty seaweed problem, and tourists are staying away," 16 July 2019 But the sargassum is now home to objects wholly unnatural too. Arwa Damon, CNN, "Microplastics discovered in 'extreme' concentrations in the North Atlantic," 19 Aug. 2019 The Caribbean, Gulf of Mexico and Florida have been plagued with the sargassum algae for several years. Andrea Navarro,, "Cancun has a nasty seaweed problem, and tourists are staying away," 16 July 2019 Journey Mexico has a blog with updates on Mexico beach sargassum levels. Adrienne Jordan, USA TODAY, "Should you travel this summer to Mexico amid safety, algae and political concerns?," 12 June 2019 As a living laboratory, the Sargasso Sea—with its masses of sargassum and their cargoes of lilliputian creatures—has yielded important findings about how and why the ocean matters to everyone, everywhere, all the time. David Doubilet, National Geographic, "The Sargasso Sea: Why it’s a living laboratory for change," 12 June 2019 But with no sense of when the onslaught of the algae, known as sargassum, will end, others are much more worried. Andrea Navarro,, "Cancun has a nasty seaweed problem, and tourists are staying away," 16 July 2019 The study says sargassum, which turns clear sea water brown, has been an issue since 2011. Marcus Lim,, "Florida’s sargassum seaweed invasion will continue, study says," 5 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sargassum.' 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 sargassum

circa 1890, in the meaning defined above

History and Etymology for sargassum

borrowed from New Latin, borrowed from Portuguese sargaço sargasso

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Last Updated

3 Oct 2019

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Time Traveler for sargassum

The first known use of sargassum was circa 1890

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