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 Word OriginOld 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.