Thesaurus

fast

adjective

Synonyms and Antonyms of fast

  1. 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. 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, faithful, good, loyal, pious, staunch (also stanch), steadfast, steady, true, true-blueRelated 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, seriousNear Antonyms irresponsible, undependable, unreliable, untrustworthy; faltering, hesitant, vacillating, wavering; dubious, irresolute, shaky, uncertain; apathetic, dispassionate, uninterestedAntonyms disloyal, faithless, false, fickle, inconstant, perfidious, recreant, traitorous, treacherous, unfaithful, untrue

  3. 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> Synonyms tight, firm, frozen, jammed, lodged, set, snug, stuck, wedgedRelated Words bonded, cemented, glued; anchored, clamped; embedded (also imbedded), entrenched (also intrenched), impacted, implanted; attached, bound, fastened, secured; immovable, unyieldingNear Antonyms detached, dislodged, freed, loosened, unattached, unbound, undone, unfastened, unsecured; movable (or moveable), yieldingAntonyms insecure, loose

  4. 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, dishonest, fraudulent, guileful, rogue, shady, sharp, shifty, underhand, underhandedRelated 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, treacherousNear Antonyms conscientious, decent, ethical, honorable, just, scrupulous, upright; forthright, straightforwardAntonyms aboveboard, honest, straight

  5. 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> Synonyms bombproof, stable, firm, sound, stalwart, strong, sturdyRelated Words dependable, durable, reliable; infrangible, irrefragable, unbreakable; beefy, solid; cohesive, toughNear Antonyms infirm, insecure, weak; shaky, tottering, tottery, unbalanced, wobbly (also wabbly); unsubstantialAntonyms rickety, unsound, unstable, unsteady

  6. 6 not lasting for a considerable time <after a fast explanation of the procedure, we were turned loose to do the work> Synonyms brief, short, littleRelated 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-termNear Antonyms endless, everlasting, interminable, persistent, unending; longish, overlong, prolonged, protracted; permanent; enlarged, expanded, supplemented; long-range, long-termAntonyms extended, far, great, lengthy, long, long-drawn-out (or long-drawn), long-lived

  7. 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, intelligent, hyperintelligent, keen, nimble, quick, quick-witted, sharp, sharp-witted, smart, supersmart, ultrasmartRelated 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, reasonableNear 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), zanyAntonyms 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


fast

adverb

Synonyms and Antonyms of fast

  1. 1 with great speed <run as fast as you can to get help> Synonyms apace, briskly, chop-chop, double-quick, fleetly, full tilt, hastily, hell-for-leather, hot, lickety-split, posthaste, presto, pronto, quick, quickly, rapidly, snappily, soon, speedily, swift, swiftly Related Words immediately, promptly, readily; impetuously, impulsively, rashly, recklessly; abruptly, suddenly; energetically, vigorously Phrases a mile a minute, at full throttle, at full tilt, by leaps and bounds, in a hurry, in short order, like a shot, like gangbusters, like wildfire Near Antonyms laggardly, lingeringly, ploddingly, sluggishly; deliberately, leisurely; belatedly, delinquently, tardily Antonyms slow, slowly

  2. 2 to a full extent or degree <everyone in camp was fast asleep within minutes of hitting the sack> Synonyms all, all of, all over, altogether, clean, completely, dead, enough, entire, entirely, even, exactly, fully, flat, full, heartily, out, perfectly, plumb [chiefly dialect], quite, soundly, thoroughly, through and through, totally, utterly, well, wholly, wideRelated Words absolutely, categorically, cold, downright, hands down, plain, stone, stone-cold, unqualifiedly; basically, by and large, chiefly, generally, largely, mainly, more or less, mostly, overall, predominantly, predominately, primarily, principally, substantially; abundantly, copiously, generously, greatlyNear Antonyms barely, hardly, just, kind of, marginally, minimally, scarcely, slightly, superficially; approximately, roughly, somewhatAntonyms half, halfway, incompletely, part, partially, partly


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