Source : Webster's Revised Unabridged Dictionary (1913)

Bulkhead \Bulk"head`\, n. [See {Bulk} part of a building.]
   1. (Naut.) A partition in a vessel, to separate apartments on
      the same deck.

   2. A structure of wood or stone, to resist the pressure of
      earth or water; a partition wall or structure, as in a
      mine; the limiting wall along a water front.

   {Bulked line}, a line beyond which a wharf must not project;
      -- usually, the harbor line.

Source : WordNet®

bulkhead
     n : a partition that divides a ship or plane into compartments