The word "cold-bloodedness" refers to a lack of emotion and empathy. Its antonyms are warmth, compassion, kindness, and empathy. Warmth suggests a sense of affection and affectionate qualities in one's personality. Compassion refers to the genuine feeling of empathy towards someone who's going through a difficult time. Kindness is the act of being considerate, sympathetic, and affectionate towards others. Empathy is the ability to understand and share the feelings of others. The antonyms of cold-bloodedness can be used to describe individuals who possess a warm and compassionate personality, are understanding of others' feelings, and are kind-hearted towards those around them.