temerarious

foolishly adventurous or bold temerarious people rush in without forethought Synonyms audacious, brash, daredevil, madcap, overbold, overconfident, reckless, foolhardyRelated Words adventuresome, adventurous, bold, daring, venturesome, venturous; brave, courageous, dauntless, doughty, fearless, gallant, greathearted, gutsy, hardy, heroic (also heroical), intrepid, lionhearted, manful, stalwart, stout, stouthearted, undauntable, undaunted, valiant, valorous; hotheaded; impetuous, imprudent, impulsive, incautious, rash; brainless, foolish, harebrained, scatterbrained; careless, heedless, thoughtless; hasty, headlong, precipitateNear Antonyms unadventurous, unambitious; fainthearted, fearful, mousy (or mousey), scary, shy, skittish, timid, timorous; calm, cool, levelheaded, sensible; alert, intelligent, quick-witted, sharp; chicken, chickenhearted, cowardly, craven, dastardly, lily-livered, pusillanimous, recreant, spineless, unheroic, yellowAntonyms careful, cautious, circumspect, guarded, heedful, prudent, safe, wary