noun

• (archaic) The action of holding the tip of a finger against the thumb and then releasing it with a snap; a flick.
  "And let him ſuppoſe, that if a Man in the beginning of the World, or four or five hundred Years ago, had laid a little round Marble upon a Table, and to put the ſame in Motion, had given it a Fillip with his Finger; the ſaid Marble, according to the abovemention'd Law of Nature, would (if no other Force had oppos'd its Motion) have moved to this very Minute with the ſame Velocity in a Right-Line, and without ceaſing, would have continued to run in the ſame Line ſuch a Length, as no Man could determine the end of."
• (by extension) Something unimportant, a trifle; also, the brief time it takes to flick one's finger (see noun sense 1); a jiffy.
  "Eat, drink and love; the rest's not worth a fillip."
• (by extension) Something that excites or stimulates.
  "This measure gave a fillip to the housing market."

verb

• (transitive) To strike, project, or propel with a fillip (that is, a finger released quickly after being pressed against the thumb); to flick.
  "Mene[laus]. An odde man Lady, euery man is odde. / Creſ[ſida]. No Paris is not, for you know tis true, / That you are odde and he is euen with you. / Mene. You fillip me a'th head."
• (transitive, by extension) To project quickly; to snap.
  "Yet he obſerv'd how ſtill his Iron Balls / Recoyl'd in vain againſt our Oaken Walls. / How the hard Pellets fell away as dead, / By our inchanted Timber fillipped."
• (transitive, by extension) To strike or tap smartly.
  "[I]t was almost, if not quite as fine in Napoleon, hitting the Frenchmen between wind and water, filliping their chivalry on the one hand, by absolutely disbelieving that so many would go about to kill one man, and catching their admiration of courage on the other, by affecting to consider them as too few to intimidate him: [...]"
• (transitive, figuratively) To drive as if by a fillip (noun sense 1); to excite, stimulate, whet.
  "The spicy aroma filliped my appetite."