once and for all

If something happens once and for all, it happens completely or finally.

如果某件事once and for all地发生了，那么就是说它彻底或终于发生了。翻译为：彻底了结地、一劳永逸地

Our intention is to destroy their offensive capability once and for all.

我们的目的是彻底摧毁他们的进攻能力。

The tone of her voice was designed to stamp on this topic of conversation once and for all.

她故意用那样的语气说话，就是想彻底结束这个话题。