The Collaborative International Dictionary of English v.0.48:

Shifter \Shift"er\, n.
   1. One who, or that which, shifts; one who plays tricks or
      practices artifice; a cozener.
      [1913 Webster]

            'T was such a shifter that, if truth were known,
            Death was half glad when he had got him down.
                                                  --Milton.
      [1913 Webster]

   2. (Naut.) An assistant to the ship's cook in washing,
      steeping, and shifting the salt provisions.
      [1913 Webster]

   3. (Mach.)
      (a) An arrangement for shifting a belt sidewise from one
          pulley to another.
      (b) (Knitting Mach.) A wire for changing a loop from one
          needle to another, as in narrowing, etc.
          [1913 Webster]

   4. (construction, tunneling) A foreman responsible for the
      work on one shift in one area, as in one heading[4].
      [RDH]

WordNet (r) 3.0 (2006):

shifter
    n 1: a stagehand responsible for moving scenery [syn:
         sceneshifter, shifter]
    2: a mechanical device for engaging and disengaging gears; "in
       Britain they call a gearshift a gear lever" [syn:
       gearshift, gearstick, shifter, gear lever]