nonchalant
Pronunciation:
/ˈnɒn.ʃəl.ənt//ˌnɑn.ʃəˈlɑnt/adjective
Definitions
Casually calm and relaxed.
Example: We handled the whole frenetic situation with a nonchalant attitude.
Indifferent; unconcerned; behaving as if detached.
Example: He is far too nonchalant about such a serious matter.