(archaic) The action of holding the tip of a finger against the thumb and then releasing it with a snap; a flick.

A sharp strike or tap made using this action, or (by extension) by other means.

(by extension) Something unimportant, a trifle; also, the brief time it takes to flick one's finger (see noun sense 1); a jiffy.

(by extension) Something that excites or stimulates.

(transitive) To strike, project, or propel with a fillip (that is, a finger released quickly after being pressed against the thumb); to flick.

(transitive, by extension) To project quickly; to snap.

(transitive, by extension) To strike or tap smartly.

(transitive, figuratively) To drive as if by a fillip (noun sense 1); to excite, stimulate, whet.

(transitive, intransitive) To make a fillip (noun sense 1) (with the fingers).