The Collaborative International Dictionary of English v.0.48:
Limber \Lim"ber\ (l[i^]m"b[~e]r), n. [For limmer, Icel. limar
   branches, boughs, pl. of lim; akin to E. limb. See Limb a
   branch.]
   1. pl. The shafts or thills of a wagon or carriage. [Prov.
      Eng.]
      [1913 Webster]
   2. (Mil.) The detachable fore part of a gun carriage,
      consisting of two wheels, an axle, and a shaft to which
      the horses are attached. On top is an ammunition box upon
      which the cannoneers sit.
      [1913 Webster]
   3. pl. (Naut.) Gutters or conduits on each side of the
      keelson to afford a passage for water to the pump well.
      [1913 Webster]
   Limber boards (Naut.), short pieces of plank forming part
      of the lining of a ship's floor immediately above the
      timbers, so as to prevent the limbers from becoming
      clogged.
   Limber box or Limber chest (Mil.), a box on the limber
      for carrying ammunition.
   Limber rope, Limber chain or Limber clearer (Naut.), a
      rope or chain passing through the limbers of a ship, by
      which they may be cleared of dirt that chokes them.
      --Totten.
   Limber strake (Shipbuilding), the first course of inside
      planking next the keelson.
      [1913 Webster]