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]

The Collaborative International Dictionary of English v.0.48:

Toggle \Tog"gle\, v. t. (Computer programming)
   To change the value of (a program variable) by activating a
   toggle switch; as, to toggle the view from character to
   graphic mode; to toggle the keyboard input from insert to
   overtype mode.
   [PJC]

   Toggle iron, a harpoon with a pivoted crosspiece in a
      mortise near the point to prevent it from being drawn out
      when a whale, shark, or other animal, is harpooned.

   Toggle joint, an elbow or knee joint, consisting of two
      bars so connected that they may be brought quite or nearly
      into a straight line, and made to produce great endwise
      pressure, when any force is applied to bring them into
      this position.

WordNet (r) 3.0 (2006):

toggle
    n 1: any instruction that works first one way and then the
         other; it turns something on the first time it is used and
         then turns it off the next time
    2: a hinged switch that can assume either of two positions [syn:
       toggle switch, toggle, on-off switch, on/off switch]
    3: a fastener consisting of a peg or pin or crosspiece that is
       inserted into an eye at the end of a rope or a chain or a
       cable in order to fasten it to something (as another rope or
       chain or cable)
    v 1: provide with a toggle or toggles
    2: fasten with, or as if with, a toggle
    3: release by a toggle switch; "toggle a bomb from an airplane"

Moby Thesaurus II by Grady Ward, 1.0:

80 Moby Thesaurus words for "toggle":
   ankle, articulate, articulation, batten, batten down, bolt,
   boundary, buckle, butt, button, cervix, clasp, cleat, clinch, clip,
   closure, connecting link, connecting rod, connection, coupling,
   deck out, doll up, dovetail, dress up, elbow, embrace, fix up,
   gliding joint, gussy up, hasp, hinge, hinged joint, hip, hitch,
   hook, interface, jam, join, joining, joint, juncture, knee,
   knuckle, latch, link, lock, miter, mortise, nail, neck, peg, pin,
   pivot, pivot joint, rabbet, rivet, scarf, screw, seam, sew,
   shoulder, skewer, slick, smarten up, snap, spiff, spruce up,
   staple, stick, stitch, suture, symphysis, tack, tie rod,
   toggle joint, union, wedge, weld, wrist, zipper



The Jargon File (version 4.4.7, 29 Dec 2003):

toggle
 vt.

    To change a bit from whatever state it is in to the other state; to
    change from 1 to 0 or from 0 to

    1. This comes from ?toggle switches?, such as standard light switches,
    though the word toggle actually refers to the mechanism that keeps the
    switch in the position to which it is flipped rather than to the fact that
    the switch has two positions. There are four things you can do to a bit:
    set it (force it to be 1), clear (or zero) it, leave it alone, or toggle
    it. (Mathematically, one would say that there are four distinct
    boolean-valued functions of one boolean argument, but saying that is much
    less fun than talking about toggling bits.)


The Free On-line Dictionary of Computing (30 December 2018):

toggle

   To change a bit from whatever state it is in to the other
   state; to change from 1 to 0 or from 0 to 1.  This comes from
   "toggle switches", such as standard light switches, though the
   word "toggle" actually refers to the mechanism that keeps the
   switch in the position to which it is flipped rather than to
   the fact that the switch has two positions.  There are four
   things you can do to a bit: set it (force it to be 1), clear
   (or zero) it, leave it alone, or toggle it.

   [Jargon File]

   (1994-12-12)