flippancy
🇺🇸
/ˈflɪpənsi/
🇬🇧
/ˈflɪpənsi/
A lack of seriousness or respect, often shown by joking or being too casual.
Despite the serious situation, his flippancy was evident as he made light of the issue.
深刻な状況にもかかわらず、彼の軽薄さは問題を軽視している様子から明らかだった。