apathy
A lack of interest or caring about things around you.
Apathy is a lack of interest, enthusiasm, or concern about something. When someone shows apathy toward their schoolwork, they don't care whether they learn anything or how their grades turn out. When voters feel apathy about an election, they can't be bothered to show up and vote.
The word suggests a deeper, more persistent absence of caring than temporary boredom. Apathy means feeling nothing about things that would normally spark some reaction, like when a student sits through an exciting science experiment completely unmoved, or when someone hears about a friend's problem and just shrugs. You can feel apathetic about one thing while caring deeply about something else: a talented musician might practice piano for hours every day but feel complete apathy toward sports.
Apathy can spread to things that truly matter. A team that feels apathy about winning will lose. A community where everyone feels apathy about local problems will watch those problems grow worse. The opposite of apathy is genuine investment: caring enough to pay attention, ask questions, and take action.