There are several antonyms that could be used for the phrase "hath a hunch," including "certain," "assured," "guaranteed," and "confident." These words all convey a sense of knowing or being sure about something, whereas "hath a hunch" suggests a feeling or intuition without certainty. Other antonyms that could be used include "doubtful," "uncertain," "hesitant," or "skeptical." These words indicate a lack of confidence or trust in one's own instincts or knowledge. Depending on the context in which "hath a hunch" is being used, any of these antonyms could be used to convey a range of different meanings and moods.