insouciant (
http://definr.com/insouciant)
adj : 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" [syn:
casual,
nonchalant]