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gulf·weedalso gulf weed (gŭlf′wēd′)
Any of several brownish seaweeds of the genus Sargassum having rounded air bladders and often forming dense, floating masses in the Atlantic Ocean. Also called sargasso, sargassum.
[After the Gulf ofMexico.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.