one bad apple can spoil the barrel

In real, traceable use. Part of the curated seed collection; community review is coming.

Meaning · English

One bad person or element can have a harmful influence on many others.

Nghĩa · Tiếng Việt

Một người hoặc yếu tố xấu có thể gây ảnh hưởng có hại đến nhiều người khác

Machine-translated — suggest a fix

Where it’s used: Used American English

Examples

One of our kittens started chewing on the chair the other day and now they're all doing it! Just goes to show that one bad apple can spoil the barrel.

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).

Common questions

What does “one bad apple can spoil the barrel” mean?

One bad person or element can have a harmful influence on many others.

Is “one bad apple can spoil the barrel” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.