indifference; lack of concern
His nonchalance is just an act: he actually cares deeply about people and things, but pretends not to care in order to protect himself.
anuj: abbey helmet to pehen le me: no worries, dad is in govt. NO CHALAAN for me, anuj: man don't be so nonchalance nonchalance rhymes like No + Challenge, When there is no challenge, people tend not to care and there will be a casual lack of concern. Chalan (Govt). Fine. so unchalance. not concerned