Source : Webster's Revised Unabridged Dictionary (1913)

Dolly \Dol"ly\, n.; pl. {Dollies}.
   1. (Mining) A contrivance, turning on a vertical axis by a
      handle or winch, and giving a circular motion to the ore
      to be washed; a stirrer.

   2. (Mach.) A tool with an indented head for shaping the head
      of a rivet. --Knight.

   3. In pile driving, a block interposed between the head of
      the pile and the ram of the driver.

   4. A small truck with a single wide roller used for moving
      heavy beams, columns, etc., in bridge building.

   5. A compact, narrow-gauge locomotive used for moving
      construction trains, switching, etc.