# rat out

CEFR B2 · Phrasal verb

Source: https://englishreference.com/word/rat-out
Updated: 2026-10-22

## Definition

to tell an authority figure about something bad that another person did. You use this when someone betrays a friend to stay out of trouble.

For teachers: to inform on someone to an authority, often to gain a personal advantage or avoid punishment. The verb is transitive and typically takes the person being betrayed as the direct object.

## Examples

- He promised not to rat out his brother for the mess.
- The suspect decided to rat out his partners in exchange for a lighter sentence from the prosecutor.
- Under intense pressure from the investigators, the whistleblower finally agreed to rat out the executives involved in the price-fixing scandal.

## Pitfalls

- Not "He ratted out the theft to the police." but "He ratted out his friend to the police." — the object of 'rat out' must be the person who committed the act, not the act itself.

## Usage notes

- often used with the preposition 'to' to indicate the person receiving the information.
- Teaching tip: anchor the meaning using the negative cultural image of a rat as a sneaky or untrustworthy animal.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.