Wrack, n.
1. Wreck; ruin; destruction. [Obs.] --Chaucer. “A world devote to universal wrack.”
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.