—v.i. 1. Informal.to toy; fool (usually fol. by with): The kids have been diddling with the controls on the television set again. 2. to waste time; dawdle (often fol. by around): You would be finished by now if you hadn't spent the morning diddling around. 3. Informal.to move back and forth with short rapid motions.
—v.t. 1. Informal.to move back and forth with short rapid motions; jiggle: Diddle the switch and see if the light comes on. 2. Slang. a. to copulate with.
b. to practice masturbation upon.