gulfweed

American  

[guhlf-weed] / ˈgʌlfˌwid /

noun

1. a coarse, olive-brown, branching seaweed, Sargassum bacciferum, common in the Gulf Stream and tropical American seas, characterized by numerous berrylike air vessels.

2. any seaweed of the same genus.

---

gulfweed British  

/ ˈɡʌlfˌwiːd /

noun

1. Also called: sargasso.   sargasso weed.  any brown seaweed of the genus Sargassum, esp S. bacciferum, having air bladders and forming dense floating masses in tropical Atlantic waters, esp the Gulf Stream

---

Etymology

Origin of gulfweed

First recorded in 1665–75; gulf + weed ¹

Example Sentences

Since 2011, scientists have tracked the recurring appearance of the Great Atlantic Sargassum Belt, a massive band of gulfweed that moves from the equator toward the Caribbean during periods of strong easterly winds.

From Science Daily • Nov. 19, 2025

This gulfweed, the swimming gulfweed or berry carrier, is the chief substance making up this immense shoal.

From Twenty Thousand Leagues Under the Sea by Walter, F. P.

The name Sargasso comes from the Spanish word sargazo, meaning gulfweed.

From Twenty Thousand Leagues Under the Sea by Walter, F. P.

Related Words

• algae