Slab \Slab\, n. [OE. slabbe, of uncertain origin; perhaps
   originally meaning, a smooth piece, and akin to slape, Icel.
   sleipr slippery, and E. slip, v. i.]
   1. A thin piece of anything, especially of marble or other
      stone, having plane surfaces. --Gwilt.
      [1913 Webster]

   2. An outside piece taken from a log or timber in sawing it
      into boards, planks, etc.
      [1913 Webster]

   3. (Zool.) The wryneck. [Prov. Eng.]
      [1913 Webster]

   4. (Naut.) The slack part of a sail.
      [1913 Webster]

   Slab line (Naut.), a line or small rope by which seamen
      haul up the foot of the mainsail or foresail. --Totten.
      [1913 Webster]