rotten apple

Idioms  

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).

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Example Sentences

By the time the homicidal aberration tears out of her like an angry insect from a rotten apple, Matty’s fate is already sealed.

From Salon

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

From BBC

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.

From BBC

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".

From BBC

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

From Los Angeles Times