• WordNet 3.6
    • n fucoid any of various algae of the family Fucaceae
    • n fucoid a fossilized cast or impression of algae of the order Fucales
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Webster's Revised Unabridged Dictionary
    • n Fucoid (Bot) A plant, whether recent or fossil, which resembles a seaweed. See Fucoid a.
    • a Fucoid (Bot) Properly, belonging to an order of alga: (Fucoideæ) which are blackish in color, and produce oöspores which are not fertilized until they have escaped from the conceptacle. The common rockweeds and the gulfweed (Sargassum) are fucoid in character.
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Century Dictionary and Cyclopedia
    • fucoid Pertaining to or resembling seaweeds, especially those belonging to the Fucaceæ; also applied to species of Phæosporeæ, which are sometimes classed as Fucoideæ.
    • fucoid Containing or characterized by impressions of fucoids or by markings resembling those made by fucoids. Also fucoidal, fucous. Thus, the “fucoidal sandstone” of Sweden is characterized by various markings of this kind. The cauda galli grit of New York exhibits forms curving like the feathers of a cock's tail, to which the name of Fucoides cauda galli was originally given, but which are now referred to the genus Taonurus.
    • n fucoid An alga belonging to the Fucoideæ—that is, to the Fucaceæ or to the Phæosporeæ.
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Chambers's Twentieth Century Dictionary
    • n Fucoid fossil seaweed
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Webster's Revised Unabridged Dictionary
Fucus, + -oid,
Chambers's Twentieth Century Dictionary
L. fucus, seaweed.


In literature:

There can be little doubt that it is a fucoid.
"The Testimony of the Rocks" by Hugh Miller
A splintered fissure held delicate fucoid impressions in fine script full of meaning.
"The Phantoms of the Foot-Bridge and Other Stories" by Charles Egbert Craddock