Definition of: fucoid

(fy′koid) adjective
1. Resembling or belonging to seaweeds; of the family Fucaceae which includes the rockweeds.
2. Containing fucoids or impressions of them. Also fu·coi′·dal, fu′cous.
—noun
1. A large, coarse, olive–brown seaweed.
2. A plant, either living or fossil, that resembles a seaweed.