Ill-mannered is a word used to describe someone who is impolite or has bad manners. The opposite of ill-mannered is well-mannered, which means having good manners or behaving in a polite and respectful manner. Well-mannered people are courteous, considerate, and thoughtful towards others. They exhibit good etiquette and always use proper social conduct. Another antonym for ill-mannered is polite, which denotes showing respect and consideration towards others. A polite person always uses courteous and gracious language and is kind and gentle in their dealings with others. A third antonym for ill-mannered is civilized, which implies a high level of culture, refinement, and sophistication.