/ Dictionary / Index S seaweed: Meaning and Definition of Find definitions for: sea•weed Pronunciation: (sē'wēd"), [key] — n. any plant or plants growing in the ocean. a marine alga. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: seaweed (Thesaurus) seaway seaweed marquetry Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language