Source : Webster's Revised Unabridged Dictionary (1913)

Driver \Driv"er\, n. [From {Drive}.]
   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 locomotive.

   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:
      (a) The driving wheel of a locomotive.
      (b) An attachment to a lathe, spindle, or face plate to
          turn a carrier.
      (c) A crossbar on a grinding mill spindle to drive the
          upper stone.

   5. (Naut.) The after sail in a ship or bark, being a
      fore-and-aft sail attached to a gaff; a spanker. --Totten.

   {Driver ant} (Zo["o]l.), 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.

Source : WordNet®

driver ant
     n : tropical nomadic ant that preys mainly on other insects
         [syn: {army ant}, {legionary ant}]