The word "un couth" refers to someone or something that is lacking in refinement or social grace. Some antonyms for "un couth" would be sophisticated, cultured, polished, elegant, refined, or graceful. A person who is "un couth" may behave in a rude or unrefined manner, while someone who is sophisticated would have refined manners and an appreciation for culture and the arts. The term "un couth" could also describe someone with poor hygiene or clothing, making the antonyms neater, tidier, cleaner, or well-dressed. Whatever the opposite of "un couth" may be, it refers to someone who is polished and refined in their behavior and appearance.