(capable of) acting, moving etc, taking a short time

speedy

deep and thorough; of a word giving force and emphasis

exhaustive

(of an activity, movement) done in a short time; enthusiastic and intelligent

fast, speedy

moving, happening, very quickly

very quick

happening unexpectedly, quickly, without warning

unexpected; happening quickly

(of speed) faster that that of sound; (of a plane) able to fly at supersonic speed

fast, quick

(of sound waves) above normal human hearing

fast, quick