Muttonheads is a derogatory term used to describe someone who is stupid or foolish. There are several antonyms for this word, which reflect different shades of intelligence and wisdom. Some of the opposite words for muttonheads include astute, clever, sagacious, shrewd, smart, and wise. These words describe individuals who are sharp-witted, quick-thinking, and can analyze situations effectively. They are attentive and observant, and can make informed decisions based on their knowledge and experience. By using these antonyms, we can describe people who are the opposite of muttonheads - individuals who can think critically, act intelligently, and make the right choices in life.