The Collaborative International Dictionary of English v.0.48:

Wasteboard \Waste"board`\, n. (Naut.)
   See Washboard, 3.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Washboard \Wash"board`\, n.
   1. A fluted, or ribbed, board on which clothes are rubbed in
      washing them.
      [1913 Webster]

   2. A board running round, and serving as a facing for, the
      walls of a room, next to the floor; a mopboard.
      [1913 Webster]

   3. (Naut.) A broad, thin plank, fixed along the gunwale of
      boat to keep the sea from breaking inboard; also, a plank
      on the sill of a lower deck port, for the same purpose; --
      called also wasteboard. --Mar. Dict.
      [1913 Webster]