Hyperintelligent is a term used to describe someone who is exceptionally intelligent or very smart. However, there are certain circumstances in which one might want to convey the opposite meaning. In such cases, antonyms of hyperintelligent can be useful. The antonyms of hyperintelligent include dumb, foolish, stupid, unwise, and unintelligent. These words describe people who are not clever or bright, and may struggle with making good decisions. These antonyms can be used in situations where it is important to emphasize that someone is not intellectually gifted or capable of critical thinking. It is important to use antonyms carefully, as these words can carry negative connotations and may hurt someone's feelings.