knell
noun /nel/
/nel/
(also death knell)
[singular]- an event that means that the end or destruction of something will come soon
丧钟；死亡的征兆；预示毁灭的事件 词源Old English cnyll (noun), cnyllan (verb), of West Germanic origin; related to Dutch knal (noun), knallen (verb) ‘bang, pop, crack’. The current spelling (dating from the 16th cent.) is perhaps influenced by bell.