adventurous
adventuresome, audacious, bold, dangerous, daredevil, daring, enterprising, foolhardy, have-a-go (informal) hazardous, headstrong, intrepid, rash, reckless, risky, temerarious (rare) venturesome
Antonyms
careful, cautious, chary, circumspect, hesitant, prudent, safe, tentative, timid, timorous, unadventurous, wary