Source : Webster's Revised Unabridged Dictionary (1913)

Gimbal \Gim"bal\, or Gimbals \Gim"bals\, n. [See {Gimmal}, n.]
   A contrivance for permitting a body to incline freely in all
   directions, or for suspending anything, as a barometer,
   ship's compass, chronometer, etc., so that it will remain
   plumb, or level, when its support is tipped, as by the
   rolling of a ship. It consists of a ring in which the body
   can turn on an axis through a diameter of the ring, while the
   ring itself is so pivoted to its support that it can turn
   about a diameter at right angles to the first.

   {Gimbal joint} (Mach.), a universal joint embodying the
      principle of the gimbal.

   {Gimbal ring}, a single gimbal, as that by which the cockeye
      of the upper millstone is supported on the spindle.

Source : WordNet®

gimbals
     n : an appliance that allows an object (such as a ship's
         compass) to remain horizontal even as its support tips