Noun: unconcern ,ún-kun'surn
- A feeling of lack of concern
"His unconcern about the danger worried his friends"
- The trait of remaining calm and seeming not to care; a casual lack of concern
"He responded to the criticism with unconcern, shrugging it off";
- nonchalance, indifference
Derived forms: unconcerns
Type of: carefreeness, feeling
Antonym: concern