# when pigs fly

idiom

Source: https://englishreference.com/idiom/when-pigs-fly
Updated: 2026-08-10

## Meaning

Never.

## Examples

- He will apologize when pigs fly.
- You can expect him to finish that report on time when pigs fly.
- The politician promised to lower taxes for everyone, but we all knew that would happen only when pigs fly.

## Origin

A reference to the physical reality that the pig possesses no wings and is incapable of flight. The image of the flying pig has served as a standard English rhetorical device for impossibility since at least the 17th century.

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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.