The word "welladvised" is often used to describe something that is wise or prudent. Its antonyms, on the other hand, describe the opposite - something that is unwise or imprudent. Some common antonyms for "welladvised" include foolish, unwise, reckless, hasty, and impulsive. These words suggest that the action or decision being made is not carefully thought out or may have negative consequences. Choosing to ignore good advice or acting without considering the consequences can lead to poor outcomes. It's important to consider all options and seek out advice and guidance, rather than acting impulsively and regretting it later.