the trait of remaining calm and seeming not to care; a casual lack of concern
(nonchalant) casual: marked by blithe unconcern; "an ability to interest casual students"; "showed a casual disregard for cold weather"; "an utterly insouciant financial policy"; "an elegantly insouciant manner"; "drove his car with nonchalant abandon"; "was polite in a teasing nonchalant manner"
(nonchalantly) coolly: in a composed and unconcerned manner; "without more ado Barker borrowed a knife from his brigade Major and honed it on a carborundum stone as coolly as a butcher"
(nonchalantly) casually: in an unconcerned manner; "glanced casually at the headlines"
Nonchalant is a singer, rapper, and songwriter from Washington, D.C. She had a hit in 1996 with the gold single "5 O'clock", which peaked at #20 on the Billboard 200.
indifference; carelessness; coolness
(nonchalant) Casually calm and relaxed; Indifferent; unconcerned; behaving as if detached
Etymologically, nonchalant comes from the French expression for "not hot under the collar." This is not the same thing, however, as being "cool," if by that term you mean blasé, sophisticated indifference. Nonchalance is instead a stylish form of engaged detachment. ...