fillip
n
1 something that adds stimulation or enjoyment
2 the action of holding a finger towards the palm with the thumb and suddenly releasing it outwards to produce a snapping sound
3 a quick blow or tap made by a finger snapped in this way
vb
4 tr to stimulate or excite
5 tr to strike or project sharply with a fillip
6 intr to make a fillip
(C15 philippe, of imitative origin)