Sprightly (adjective)(sprahyt-lee)
Animated, vivacious, or gay; lively.
The ballerina stepped sprightly across the stage.
Insouciance (noun)( in-soo-see-uhns)
1. The quality of being insouciant
2. Lack of care or concern
I told him the news, so I was rather taken aback when he reacted with such insouciance as if nothing had happened.
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