Not easily excited, even under pressure
Dean answered in a voice as nonchalant as he could muster.
The animals had a nonchalant air of "What are you doing here, humans?" about them.
Have you been too nonchalant about your own legacy?
The nonchalant reply of Miller was a simple "yeah."
Adrienne shucked her coat and tried to act nonchalant in spite of the warmth in her cheeks.