adjective
fast, speedy
Synonyms: abrupt, accelerated, active, agile, alert, a move on, animated, ASAP, breakneck, brief, brisk, cursory, curt, double time, energetic, expeditious, expeditive, express, fleet, flying, going, harefooted, hasty, headlong, hurried, immediate, impatient, impetuous, instantaneous, keen, lively, mercurial, move it, nimble, on the double, perfunctory, posthaste, prompt, pronto, rapid, snappy, spirited, sprightly, spry, sudden, swift, the lead out, winged
Antonyms: lazy, slow, sluggish
adjective
smart
Synonyms: able, active, acute, adept, adroit, all there, apt, astute, bright, canny, capable, clever, competent, deft, dexterous, discerning, effective, effectual, intelligent, keen, knowing, nimble-witted, on the ball, perceptive, perspicacious, prompt, quick on the draw, quick on the trigger, quick on the uptake, quick-witted, ready, receptive, savvy, sharp, sharp as a tack, shrewd, skillful, slick, smart as a whip, vigorous, whiz, wired, wise
Antonyms: ignorant, slow, stupid, uneducated