Insouciant means carefree, and untroubled by what should worry you. An insouciant shrug, insouciant charm, insouciant about the deadline.
It is admiring and disapproving at once, since the untroubled part is stylish and the what should worry you part is not. The French is simply not worrying, and English borrowed it in 1828 because it had no equivalent.
1adjectiveinsouciantCarefree, and untroubled by what should worry you.
“He strolled into the exam an hour late, looking completely insouciant.”
insouciant is a quality.
French insouciant is in-, not, plus souciant, worrying.
French
insouciant
English, today
insouciant
Built from
From French insouciant, from in- (“not”) + souciant (“worrying”), 1828.
Etymology from Wiktionary, CC BY-SA