death knell

noun

1. a harbinger of the end, death, or destruction of something.

2. passing bell.

death knell

noun

1. something that heralds death or destruction

2. a bell rung to announce a death

Idioms and Phrases

Something that indicates impending failure, as in His low scores sounded the death knell for his ambitions. The noun knell, used for the ringing of a bell since at least a.d. 1000, is rarely heard today except in this figurative phrase.