the.com/insensitivity

means A lack of awareness or care for other people's feelings, often shown by what someone says or does.

from Built from Latin sensus, 'feeling' or 'sense,' via sentire, 'to feel' — the same root behind sense, sentiment, and sentimental. Add the negating in- and you get, literally, 'without feeling.' The word entered English use alongside 'sensitive' as thinkers began sorting people into those who could be wounded by words and those who, apparently, could not.