Cool Mateinformal5K
When pigs fly
UK //wɛn pɪɡz flaɪ//US //wɛn pɪɡz flaɪ//
Definition
A phrase indicating that something is impossible.
In simple words: Something that will never happen.
Examples
- I'll believe she'll clean her room when pigs fly.
- He thinks he can win the lottery, but that's like saying you'll see pigs fly.
- They expect him to apologize, but that's when pigs fly!
- She claims she'll finish the project on time, but I'll only believe it when pigs fly.
- He’ll stop making excuses when pigs fly, I’m sure of that!
Usage notes
Used to express that something is impossible or very unlikely. More appropriate in casual conversation than in formal writing.
Grammar pattern
standalone phrase
Memory hint
Imagine a pig with wings soaring through the sky—it's a funny sight, but totally impossible!
Collocations
- believe it when pigs fly
- expect it when pigs fly
- do it when pigs fly
- see it when pigs fly
Synonyms
- never
- not a chance
- impossible
- highly unlikely
- will not happen
Common mistakes
- Used in serious contexts where a straightforward answer is needed.
- Misunderstood as a literal phrase rather than an idiom.
- Incorrectly interpreted as hopeful rather than negative.