Troll

n.
  1. The act of moving round; routine; repetition.
  2. A song the parts of which are sung in succession; a catch; a round.
  3. A trolley.
    4. Troll plate (Mach.),
    a rotative disk with spiral ribs or grooves, by which several pieces, as the jaws of a chuck, can be brought together or spread radially.