Over-cautious means excessively vigilant or wary, often to the point of being timid or hesitating. Antonyms for over-cautious are words that describe individuals who are more daring, adventurous, or bold. Some possible antonyms for over-cautious are spontaneous, impulsive, risk-taker, brave, fearless, confident, bold, audacious, and adventurous. These antonyms suggest that the individuals who possess these traits are more likely to take risks, explore new possibilities, and act quickly without hesitation. By embracing their adventurous side, they may discover new opportunities that would have been missed if they had been overly cautious. Therefore, while being careful is essential, being courageous can have its rewards.