There are several antonyms for the word "un sympathetic," including empathetic, compassionate, caring, understanding, and kind-hearted. While someone who is un sympathetic lacks the ability to understand or feel empathy towards others, an empathetic person is able to easily relate to others and understand their emotions. Compassionate people are sensitive to the needs of others and express genuine concern and care. A caring person is affectionate and attentive, while an understanding person is able to grasp a person's perspective and challenges. A kind-hearted person is gentle, considerate and approachable. By understanding these antonyms, we can properly express ourselves and act more effectively in different social situations.