coffin

1. N-COUNT A coffin is a box in which a dead body is buried or cremated. 棺材

2. PHRASE If you say that one thing is a nail in the coffin of another thing, you mean that it will help bring about its end or failure. 断送

A fine would be the final nail in the coffin of the airline. 一笔罚款将最终断送该航线。