What does "kelp" mean?

Kelp: (Bot.) Any large blackish seaweed. Note: Laminaria is the common kelp of Great Britain; Macrocystis pyrifera and Nereocystis Lutkeana are the great kelps of the Pacific Ocean. Kelp crab (Zoöl.), a California spider crab (Epialtus productus), found among seaweeds, which it resembles in color. -- Kelp salmon (Zoöl.), a serranoid food fish (Serranus clathratus) of California. See Cabrilla.

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