1. <character> The tilde character.
2. <jargon> (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.
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Nearby terms: TWENEX « Twente Compiler Generator System « Twentel « twiddle » TWIG » twilight zone » twink