A reckless impetuous irresponsible person.

synonyms: daredevil, harum-scarum, hothead, lunatic, swashbuckler.

Roget 863: rashness etc. adj.; temerity, want of caution, imprudence, indiscretion; overconfidence, presumption, audacity.    precipitancy, precipitation; impetuosity; levity; foolhardihood^†, foolhardiness; heedlessness, thoughtlessness etc. (inattention) 458; carelessness etc. (neglect) 460; desperation; Quixotism, knight-errantry; fire eating.    gaming, gambling; blind bargain, leap in the dark, leap of faith, fool's paradise; too many eggs in one basket.    desperado, rashling^†, madcap, daredevil, Hotspur, fire eater, bully, bravo, Hector, scapegrace, enfant perdu [Fr.]; Don Quixote, knight-errant, Icarus; adventurer; gambler, gamester; dynamitard^†; boomer [U.S.].    ... show more

Roget 504: madman, lunatic, maniac, bedlamite^†, candidate for Bedlam, raver^†, madcap, crazy; energumen^†; automaniac^†, monomaniac, dipsomaniac, kleptomaniac; hypochondriac etc. (low spirits);; crank, Tom o'Bedlam.    dreamer etc. 515; rhapsodist, seer, highflier^†, enthusiast, fanatic, fanatico [Sp.]; exalte [Fr.]; knight errant, Don Quixote.    idiot etc. 501.    ... show more

Roget 173: violence, inclemency, vehemence, might, impetuosity; boisterousness etc. adj.; effervescence, ebullition; turbulence, bluster; uproar, callithump [U.S.], riot, row, rumpus, le diable a quatre [Fr.], devil to pay, all the fat in the fire.    severity etc. 739; ferocity, rage, fury; exacerbation, exasperation, malignity; fit, paroxysm; orgasm, climax, aphrodisia^†; force, brute force; outrage; coup de main; strain, shock, shog^†; spasm, convulsion, throe; hysterics, passion etc. (state of excitability) 825.    outbreak, outburst; debacle; burst, bounce, dissilience^†, discharge, volley, explosion, blow up, blast, detonation, rush, eruption, displosion^†, torrent.    turmoil etc. (disorder) 59; ferment etc. (agitation) 315; storm, tempest, rough weather; squall etc. (wind) 349; earthquake, volcano, thunderstorm.    berserk, berserker; fury, dragon, demon, tiger, beldame, Tisiphone^†, Megaera, Alecto^†, madcap, wild beast; fire eater etc. (blusterer) 887.    ... show more

Roget 844: humorist, wag, wit, reparteeist^†, epigrammatist, punster; bel esprit, life of the party; wit-snapper, wit-cracker, wit-worm; joker, jester, Joe Miller^†, drole de corps^†, gaillard^†, spark; bon diable [Fr.]; practical joker.    buffoon, farceur [Fr.], merry-andrew, mime, tumbler, acrobat, mountebank, charlatan, posturemaster^†, harlequin, punch, pulcinella^†, scaramouch^†, clown; wearer of the cap and bells, wearer of the motley; motley fool; pantaloon, gypsy; jack-pudding, jack in the green, jack a dandy; wiseacre, wise guy, smartass [Coll.]; fool etc. 501.    zany, madcap; pickle-herring, witling^†, caricaturist, grimacier^†; persifleur^†.    ... show more

Dutch: snoever, waaghals
Polish: artysta, egzemplarz, ptaszek, ziółko

Characterized by undue haste and lack of thought or deliberation:
— Madcap escapades.

synonyms: brainish, hotheaded, impetuous, impulsive, tearaway.

Roget 825: excitable, easily excited, in an excitable state; high-strung; irritable etc. (irascible) 901; impatient, intolerant.    feverish, febrile, hysterical; delirious, mad, moody, maggoty-headed.    unquiet, mercurial, electric, galvanic, hasty, hurried, restless, fidgety, fussy; chafing etc. v.. startlish^†, mettlesome, high-mettled^†, skittish.    vehement, demonstrative, violent, wild, furious, fierce, fiery, hot-headed, madcap.    overzealous, enthusiastic, impassioned, fanatical; rabid etc. (eager) 865.    rampant, clamorous, uproarious, turbulent, tempestuous, tumultuary^†, boisterous.    impulsive, impetuous, passionate; uncontrolled, uncontrollable; ungovernable, irrepressible, stanchless^†, inextinguishable, burning, simmering, volcanic, ready to burst forth, volatile.    excited, exciting etc. 824.    ... show more

Roget 863: rash, incautious, indiscreet; imprudent, improvident, temerarious; uncalculating^†; heedless; careless etc. (neglectful) 460; without ballast, heels over head, head over heels; giddy etc. (inattentive) 458; wanton, reckless, wild, madcap; desperate, devil-may-care.    hot-blooded, hotheaded, hotbrained^†; headlong, headstrong; breakneck; foolhardy; harebrained; precipitate, impulsive.    overconfident, overweening; venturesome, venturous; adventurous, Quixotic, fire eating, cavalier; janty^†, jaunty, free and easy.    off one's guard etc. (inexpectant) 508^†.    ... show more

Roget 842: witty, attic; quick-witted, nimble-witted; smart; jocular, jocose, humorous; facetious, waggish, whimsical; kidding, joking, puckish; playful etc. 840; merry and wise; pleasant, sprightly, light, spirituel^†, sparkling, epigrammatic, full of point, ben trovato [It]; comic etc. 853.    zany, madcap.    funny, amusing etc. (amusement) 840.    ... show more

Polish: impulsywny, popędliwy, porywczy, gwałtowny