The Collaborative International Dictionary of English v.0.48:

Toggle \Tog"gle\, n. [Cf. Tug.] [Written also toggel.]
   1. (Naut.) A wooden pin tapering toward both ends with a
      groove around its middle, fixed transversely in the eye of
      a rope to be secured to any other loop or bight or ring; a
      kind of button or frog capable of being readily engaged
      and disengaged for temporary purposes.
      [1913 Webster]

   2. (Mach.) Two rods or plates connected by a toggle joint.
      [1913 Webster]

   3. A toggle switch.
      [PJC]