/ Dictionary / Index F fucus: Meaning and Definition of Find definitions for: fu•cus Pronunciation: (fy'kus), [key] — pl. -ci -cus•es. any olive-brown seaweed or alga of the genus Fucus, having branching fronds and often air bladders. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: fucus (Thesaurus) fucoid fud Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language