‖prop. n. [ NL. See Nereid, and Cyst. ] (Bot.) A genus of gigantic seaweeds. [ 1913 Webster ]

☞ Nereocystis Lutkeana, of the North Pacific, has a stem many fathoms long, terminating in a great vesicle, which is crowned with a tuft of long leaves. The stem is used by the Alaskans for fishing lines. [ 1913 Webster ]