Insensitiveness, also called insensitivity, refers to a lack of empathy or awareness towards the feelings of others. Synonyms for this word include callousness, indifference, coldness, numbness, and apathy. Someone who is insensitive may show disregard for others' emotions, make insensitive comments, or act inconsiderately towards others. Antonyms of insensitiveness include sensitivity, caring, compassion, warmth, and empathy. It's important to recognize and address insensitiveness in oneself or others in order to maintain positive relationships and create an inclusive and respectful environment.