expression, noun
laughingstock; object of ridicule
A set phrase meaning someone or something that becomes the target of laughter or mockery. Often used with になる or にする.
彼は失敗して、みんなの物笑いの種になった。
He failed and became the laughingstock of everyone.
そんなことをしたら物笑いの種になるよ。
If you do that, you'll become a laughingstock.