rotten apple

1. A bad individual among many good ones, especially one that spoils the group. For example, The roommates are having problems with Edith—she's the one rotten apple of the bunch. This expression is a shortening of the proverb a rotten apple spoils the barrel, coming from a 14th-century Latin proverb translated as “The rotten apple injures its neighbors.” The allusion in this idiom is to the spread of mold or other diseases from one apple to the rest. In English the first recorded use was in Benjamin Franklin's Poor Richard's Almanack (1736).

Example Sentences

"It's always been a rotten apple, not a rotten barrel," she said.

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Mdluli was later sentenced to five years in jail for kidnapping, assault, and intimidation, vindicating Gen Mkhwanazi's view that he was a rotten apple within the police service.

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Jurors heard Westwood, who also appeared in the BBC's Doctors series, was a "rotten apple" and his repeated sexual offending was "a habit, a lifestyle".

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Carmen gripped The Wonderful Wizard of Oz harder as Tony kicked a rotten apple core into the gutter.

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Crypto promoters will paint Bankman-Fried as merely a single rotten apple.

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