sargassum

A genus of marine algæ, of the class Fucaceæ, having fronds attached by a disk, and branching stems with the fronds provided with a midrib and distinctly stalked air-bladders.

[lowercase] Gulfweed.

A genus of algæ including the gulf weed.

Any of many brown algae of the genus Sargassum; gulfweed.

Brown algae with rounded bladders forming dense floating masses in tropical Atlantic waters as in the Sargasso Sea.