A reddish kelp, Laminaria digitata; common tangle.

spec. The giant or great kelp (Macrocystis pyrifera or Fucus giganteus) of the Pacific coast of America, the largest of seaweeds.

A genus of brown algae of which the only species now recognized is Macrocystis pyrifera, a giant kelp which is widespread in the southern…

A thin, flat, brown seaweed of the genus so called; also known as oar-weed or kelp. Also attributive.