when pigs fly
Never.
Meaning adapted from Wiktionary, available under CC BY-SA 4.0.
“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.”
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.
- 01
couldn't stop a pig in a passage
To be bow-legged.
- 02
fly blind
To do by guesswork; to feel one's way.
- 03
fly by
To pass or go past quickly, often without much interaction
- 04
fly by the seat of one's pants
To pilot an aircraft without the aid of instruments and without a flight plan, using only instinct, visual observation, and practical judgment.
- 05
fly in the face of
To act in a manner highly contrary to; to counteract or contradict.
- 06
fly in the ointment
Something (especially a minor thing) which ruins or spoils everything else, or makes it less pleasant; a nuisance or problem; a disagreeable or unpleasant detail.
- 07
fly low
To have one's fly (zipper) undone.
- 08
fly off
To flee rapidly; to run away.
Last updated August 10, 2026