flick
To strike with a light, quick, snapping stroke of the finger. May be used to cause light pain as a punishment, such as with a forehead flick; to propel objects, such as a paper football; or to perform other various actions, such as removing a lid, lighting a match, etc.
If referring to the slang term, "flicking the bean", specifically referring to clitoral stimulation, please see female masturbation and clitoral stimulation.