Synonyms of nonchalant

Adjective

1. casual, insouciant, nonchalant, unconcerned (vs. concerned)

usage: 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"

Definition and meaning of nonchalant (Dictionary)