Synonyms and related words :
accident-prone, adventuresome, agile, airy, apathetic, ataractic, audacious, blase, brash, breakneck, carefree, careless, casual, cursory, dangerous, daredevil, daring, dashing, degage, desperate, devil-may-care, disinterested, dispassionate, disregardant, disregardful, double-quick, eagle-winged, easygoing, expeditious, express, fast, feckless, fleet, flippant, flying, foolhardy, foolish, forgetful, free and easy, furious, galloping, hair-trigger, harum-scarum, hasty, headlong, heedless, hopeless, hotheaded, hurried, hustling, ill-advised, ill-considered, ill-contrived, ill-devised, ill-gauged, ill-judged, impatient, impetuous, impolitic, imprudent, impulsive, inadvisable, inattentive, incautious, inconsiderate, incurious, indifferent, indiscreet, inexcitable, inexpedient, injudicious, insensate, insouciant, irrational, irresponsible, lackadaisical, lazy, light of heel, light-footed, listless, lively, mad, madcap, mercurial, mindless, misadvised, misguided, myopic, negligent, nimble, nimble-footed, nonchalant, oblivious, offhand, overeager, overenthusiastic, overhasty, overzealous, perfunctory, pococurante, precipitant, precipitate, precipitous, prompt, quick, quick as lightning, quick as thought, rapid, rash, reasonless, regardless, respectless, running, senseless, shortsighted, slap-bang, slapdash, snappy, spanking, speedy, sudden, swift, tactless, temerarious, thoughtless, turned-off, unadvised, unanxious, unconcerned, unconsidered, undiplomatic, undiscerning, undiscriminating, unforeseeing, unheedful, unheeding, uninterested, unmindful, unprepared, unready, unreasonable, unreflecting, unreflective, unseeing, unsensible, unsolicitous, unsound, untactful, unthinking, unthoughtful, unwise, venturesome, venturous, wanton, wild, winged, witless