Thesaurus
fast
adjective
Synonyms and Antonyms of FAST
1
moving, proceeding, or acting with great speed <the fast pace of construction resulted in our new house being done ahead of schedule>
Synonyms blistering, breakneck, breathless, brisk, dizzy, fleet, fleet-footed, flying, galloping, hasty, hot, lightning, nippy, quick, rapid, rapid-fire, rattling, snappy, speedy, splitting, swift, whirlwind, zippy
Related Words expeditious, prompt, ready; accelerated, hastened, hurried, quickened, rushed; breathtaking; energetic, strenuous, strong, vigorous; high-speed; rush; ultrafast, ultrarapid
Phrases at speed [chiefly British]
Near Antonyms crawling, dallying, dawdling, dillydallying, dragging, laggard, languid, lingering, plodding, poking, poky (or pokey), slowish, sluggish, unhurried; deliberate, leisurely, measured; dilatory, late, tardy; ultraslow
Antonyms slow
2
firm in one's allegiance to someone or something <the two girls soon became fast and inseparable friends>
Synonyms constant, dedicated, devoted, devout, down-the-line, fast, good, loyal, pious, staunch (also stanch), steadfast, steady, true, true-blue
Related Words dependable, dutiful, reliable, responsible, solid, tried, tried-and-true, trustworthy, trusty; unfaltering, unhesitating, unwavering; determined, intent, resolute; confirmed, dyed-in-the-wool, inveterate, sworn; ardent, avid, enthusiastic, fervent, fervid, gung ho, impassioned, passionate, serious
Near Antonyms irresponsible, undependable, unreliable, untrustworthy; faltering, hesitant, vacillating, wavering; dubious, irresolute, shaky, uncertain; apathetic, dispassionate, uninterested
Antonyms disloyal, faithless, false, fickle, inconstant, perfidious, recreant, traitorous, treacherous, unfaithful, untrue
3
firmly positioned in place and difficult to dislodge <the rusty, old screws are so fast in the fitting that there's no hope of getting them out>
Related Words bonded, cemented, glued; anchored, clamped; embedded (also imbedded), entrenched (also intrenched), impacted, implanted; attached, bound, fastened, secured; immovable, unyielding
4
given to or marked by cheating and deception <rolling back odometers was just one of the fast practices that the used-car dealer was guilty of>
Synonyms bent [chiefly British], crooked, deceptive, double-dealing, duplicitous, fast, fraudulent, guileful, rogue, shady, sharp, shifty, underhand, underhanded
Related Words unconscionable, unethical, unprincipled, unscrupulous; deceitful, deceiving, deluding, delusive, delusory, false; artful, beguiling, cagey (also cagy), crafty, cunning, foxy, slick, sly, subtle, wily; defrauding, devious, furtive, slippery, sneaking, sneaky, trickish, tricky; insidious, perfidious, treacherous
Near Antonyms conscientious, decent, ethical, honorable, just, scrupulous, upright; forthright, straightforward
5
marked by the ability to withstand stress without structural damage or distortion <as the storm approached, we checked to see that every thing on the outside of the house was fast and locked in position>
Related Words dependable, durable, reliable; infrangible, irrefragable, unbreakable; beefy, solid; cohesive, tough
Near Antonyms infirm, insecure, weak; shaky, tottering, tottery, unbalanced, wobbly (also wabbly); unsubstantial
6
not lasting for a considerable time <after a fast explanation of the procedure, we were turned loose to do the work>
Related Words shortish; abbreviated, abridged, curtailed, cut-back, shortened, syncopated; compact, condensed; abrupt, sudden; ephemeral, fleeting, momentary, short-lived, transient, transitory; impermanent; compendious, concise, crisp, epigrammatic, laconic, pithy, succinct, summary, terse; short-range, short-term
Near Antonyms endless, everlasting, interminable, persistent, unending; longish, overlong, prolonged, protracted; permanent; enlarged, expanded, supplemented; long-range, long-term
7
having or showing quickness of mind <I don't know how to operate this machine, but I'm a fast learner>
Synonyms alert, brainy, bright, brilliant, clever, exceptional, fast, hyperintelligent, keen, nimble, quick, quick-witted, sharp, sharp-witted, smart, supersmart, ultrasmart
Related Words apt, ingenious, resourceful; acute, astute, discerning, heady, insightful, knowing, perceptive, percipient, perspicacious, sagacious, sapient, savvy, wise; cerebral, erudite, genial, highbrow, knowledgeable, learned, literate, scholarly, well-read; educated, informed, schooled, skilled, trained; creative, inventive, judicious, prudent, sage, sane, sapient, sensible, sound, wise; crafty, cunning, foxy, shrewd, wily; logical, rational, reasonable
Near Antonyms feebleminded, simpleminded; boobish, foolish, half-baked, idiotic (also idiotical), imbecile (or imbecilic), moronic, silly; ignorant, illiterate, lowbrow, nonintellectual, unacademic, uneducated, uninformed, unintellectual, untaught, unthinking; absurd, asinine, balmy, cockeyed, crackpot, crazy, cuckoo, daffy, daft, dippy, dotty, featherheaded, fool, half-baked, harebrained, insane, kooky (also kookie), loony (also looney), lunatic, mad, nonsensical, nutty, preposterous, sappy, screwball, tomfool, unwise, wacky (also whacky), zany
Antonyms airheaded, birdbrained, boneheaded, brain-dead, brainless, bubbleheaded, chuckleheaded, dense, dim, dim-witted, doltish, dopey (also dopy), dorky [slang], dull, dumb, dunderheaded, empty-headed, fatuous, gormless [chiefly British], half-witted, knuckleheaded, lamebrain (or lamebrained), lunkheaded, mindless, obtuse, opaque, pinheaded, senseless, simple, slow, slow-witted, soft, softheaded, stupid, thick, thickheaded, thick-witted, unbrilliant, unintelligent, unsmart, vacuous, weak-minded, witless
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