The antonyms for warm-heartedness are often associated with coldness, indifference or harshness. Some possible antonyms for warm-heartedness include cruelty, malice, callousness, unsympathetic, unfeeling, cold-hearted, mean-spirited, and ruthless. These terms highlight a lack of compassion or empathy towards others, as well as a tendency to show harshness or aggression. Cold-heartedness can manifest in various ways, such as being unresponsive to other people's needs, being excessively critical or judgmental, and displaying selfish behavior. Overall, the antonyms for warm-heartedness are associated with negative emotions and behaviors that can harm relationships and undermine social cohesion.