Nonchalant
Synonyms: Calm, unconcerned, and collected, composed, indifferent, blasé, detached, casual, insouciant, cool, collected, cool as a cucumber, airy, unemotional, dispassionate, apathetic, offhand, and laid-back.
Example Sentences
He gave a nonchalant shrug yesterday.
She acted nonchalant despite the chaos.
His nonchalant attitude frustrated the team.
They remained nonchalant about the outcome.
A nonchalant smile concealed his nervousness.