Wolzogen, nonchalantly stretching his legs, approached Kutuzov with a half-contemptuous smile on his lips, scarcely touching the peak of his cap.
He treated his Serene Highness with a somewhat affected nonchalance intended to show that, as a highly trained military man, he left it to Russians to make an idol of this useless old man, but that he knew whom he was dealing with.
There are no more uses of "nonchalant" in the book.
Show samples from other sources
I could tell she was nervous, but she was trying to look nonchalant.
How could she be so nonchalant about making him suffer?