Driver

n.
  1. One who, or that which, drives; the person or thing that urges or compels anything else to move onward.
  2. The person who drives beasts or a carriage; a coachman; a charioteer, etc.; hence, also, one who controls the movements of a any vehicle.
  3. An overseer of a gang of slaves or gang of convicts at their work.
  4. (Mach.) A part that transmits motion to another part by contact with it, or through an intermediate relatively movable part, as a gear which drives another, or a lever which moves another through a link, etc. Specifically:
  5. (Naut.) The after sail in a ship or bark, being a fore-and-aft sail attached to a gaff; a spanker.
  6. An implement used for driving;
    1. The driving wheel of a locomotive.
    2. An attachment to a lathe, spindle, or face plate to turn a carrier.
    3. A crossbar on a grinding mill spindle to drive the upper stone.
    4. A mallet.
    5. A tamping iron.
    6. A cooper's hammer for driving on barrel hoops.
    7. A wooden-headed golf club with a long shaft, for playing the longest strokes.
    Driver ant (Zoöl.),
    a species of African stinging ant; one of the visiting ants (Anomma arcens); -- so called because they move about in vast armies, and drive away or devour all insects and other small animals.