no laughing matter

US /noʊ ˈlæfɪŋ ˈmætər/
UK /noʊ ˈlæfɪŋ ˈmætər/
"no laughing matter" picture
1.

笑い事ではない, 深刻な問題

a serious issue or situation that should not be treated lightly or joked about

:
The company's financial problems are no laughing matter.
会社の財政問題は笑い事ではない
Climate change is a serious threat and no laughing matter.
気候変動は深刻な脅威であり、笑い事ではない