the.com/knell

The sound a bell makes when it knows something you don't yet.

means A slow, mournful bell toll that signals death or a doom-laden ending — and by extension, any ominous sign that something is finished for good.

from From Old English 'cnyll,' rooted in a Germanic imitative base — one of those words born simply from mimicking the sound itself, the dull low strike of metal on metal. It's a cousin, loosely, of 'knock' and 'clang,' part of a family of words that just copy noise into language. By the time it settled into English, 'knell' had narrowed from any bell-stroke to specifically the tolling that announces a death — the sound, not the bell, carrying the dread.

origin
Old English cnyll, mimicking the toll itself
usage
Almost always funeral, rarely birthday
idiom
death knell means the end is audible
cousin word
related to knock, not to bell
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