Source : Webster's Revised Unabridged Dictionary (1913)

   2. Any marine vegetation cast up on the shore, especially
      plants of the genera {Fucus}, {Laminaria}, and {Zostera},
      which are most abundant on northern shores.

   3. (Bot.) Coarse seaweed of any kind.

   {Wrack grass}, or {Grass wrack} (Bot.), eelgrass.