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. (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.)

[glossary]
[Reference(s) to this entry by made by: {bit}{HCF}{twiddle}]