The antonyms for the word "is sympathetic" are "unfeeling," "unsympathetic," "harsh," "cold," "uncaring," and "indifferent." These words describe a lack of empathy, compassion, or understanding towards others. If someone is unsympathetic, they may be insensitive to the struggles or pain of others. A harsh, unfeeling person may have difficulty expressing warmth or kindness towards others. In contrast, a person who is sympathetic is able to empathize with others and offer support, understanding, and compassion. It is important to recognize and choose our words carefully, as they can have a significant impact on how we communicate and relate to others.