flick-knife

n (pl flick-knives) (US switch-blade) knife with a blade inside the handle that springs out quickly when a button is pressed 弹簧刀.

fleet, fleet admiral, Fleet Street, fleeting, fleetingly, fleetness, flesh, flesh-pots, flesh-wound, fleshly, fleshy, fleur-de-lis (also fleur-de-lys), flew, flex, flexibility, flexible, flexibly, flexitime, flibbertigibbet, flick, flicker, flier, flier (also flyer), flies, flight, flight attendant, flight lieutenant, flight path, flight sergeant, flight simulator, flight-deck, flight-recorder, flightless, flighty, flimsily, flimsiness, flimsy, flinch, fling, flint,