Not feeling or showing care, compassion, or concern for others.
From un- (not) + caring (present participle of care from Old English 'carian' meaning to sorrow or be anxious). A straightforward compound with ancient Germanic roots.
Neurologically, uncaring people often lack proper activation in the anterior cingulate cortex, the brain's empathy center—it's not always a choice, sometimes it's literally how their brain is wired.
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