What it means
A bad apple is a corrupt or troublesome individual whose bad behaviour threatens to spoil the whole group, from the old saying that one rotten apple spoils the barrel. It is the single dishonest officer, the one disruptive pupil, the lone cheat among honest colleagues. The phrase often comes up in arguments about whether the problem is just a few bad apples or something rotten throughout.
Usage examples
"One bad apple on the committee soured the mood for everyone."
"They insisted it was just one bad apple, not a problem with the whole team."
"It only takes one bad apple in the team to turn every meeting into a sulk-fest."
"They blamed one bad apple, but the whole department had been cutting the same corners for years."
Where it comes from
Straight from the old proverb that one rotten apple spoils the whole barrel, since real apples really do rot their neighbours. The phrase narrowed to mean the single bad character who drags down an otherwise decent group, and it lives on in every just a few bad apples excuse.
Other ways to say it
Editors of this term
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