[Poss. derived from frobnitz, and usually abbreviated to frob, but frobnicate is recognized as the official full form.:] To manipulate or adjust, to tweak. One frequently frobs bits or other 2-state devices. Thus: “Please frob the light switch” (that is, flip it), but also “Stop frobbing that clasp; you'll break it”. One also sees the construction to frob a frob. See tweak and twiddle.
Usage: frob, twiddle, and tweak sometimes connote points along a continuum. ‘Frob’ connotes aimless manipulation; twiddle connotes gross manipulation, often a coarse search for a proper setting; tweak connotes fine-tuning. If someone is turning a knob on an oscilloscope, then if he's carefully adjusting it, he is probably tweaking it; if he is just turning it but looking at the screen, he is probably twiddling it; but if he's just doing it because turning a knob is fun, he's frobbing it. The variant frobnosticate has been recently reported.