nip sth in the bud

Nip是掐断的意思。Bud是花蕾，萌芽的意思。nip something in the bud, 这个习惯用语意思是将一件事物消灭在萌芽状态，防微杜渐。

to stop something before it has an opportunity to become established

把…消灭在萌芽状态，对…防患于未然

Many serious illnesses can be nipped in the bud if they are detected early enough.

如果及早确诊，许多恶疾可以治愈。

It's important to nip this kind of bullying in the bud.

重要的是及早制止这种欺凌弱小的行为。