1. [n]  a series of small (usually idle) twists or turns
2. [v]  manipulate, as in a nervous or unconscious manner
3. [v]  turn in a twisting or spinning motion; "The leaves swirled in the autumn wind"

1. \Twid"dle\, v. t. [Probably of imitative origin. Cf.
   {Tweedle}.]
   To touch lightly, or play with; to tweedle; to twirl; as, to
   twiddle one's thumbs; to twiddle a watch key. [Written also
   twidle.] --Thackeray.
   

2. \Twid"dle\, v. i.
   To play with anything; hence, to be busy about trifles.
   --Halliwell.
   

3. \Twid"dle\, n.
   1. A slight twist with the fingers.
   2. A pimple. [Prov. Eng.] --Halliwell.
   

1. The tilde character.

2. (To make) a small or insignificant change. E.g. twiddling a program often fixes one bug and generates several new ones (see also shotgun debugging). Bits are often twiddled. Twiddling a switch or knob implies much less sense of purpose than toggling or tweaking it; see frobnicate. Bit twiddling connotes aimlessness, and at best doesn't specify what you're doing to the bit; to "toggle a bit" has a more specific meaning.

[Jargon File]