The antonyms for "un-friendlier" are words that describe a friendly and pleasant demeanor. The opposite of un-friendly is friendly, amiable, or affable. Someone who is friendly is kind, approachable, and welcoming towards others. They may greet people with a smile or a warm hello, and they generally make others feel at ease. Other antonyms for un-friendly are welcoming, cordial, sociable, congenial, genial, kind-hearted, and warm-hearted. A person's demeanor is important when building social connections, and being friendly is one of the best ways to form meaningful relationships. Therefore, it is essential to develop a friendly character trait that people can identify as welcoming and approachable.