'When Pigs Fly': Definition, Meaning, Examples

By Carly Forsaith, updated on September 10, 2023

What does it mean when people say 'when pigs fly?' If you've been asking yourself the same question, you've come to the right place. This article will teach you everything you need to know about the meaning of this idiom, as well as how and when to use it.

But here's the short version:

  • 'When pigs fly' is an expression used to describe something that is impossible or highly unlikely to happen.

What Does 'When Pigs Fly' Mean?

'When pigs fly' is an idiom that's commonly used to talk about a situation or event that probably won't happen. As you know, pigs can't fly, so that's why we use this figure of speech to talk about something impossible.

It's most often used as a humoristic remark, a way to gently poke fun at a statement someone just made. Or you can use it to respond to something somebody just said to express just how unlikely you think that thing will happen.

For example, imagine your friend invited you to go skydiving, and you're afraid of heights. You might respond to their invitation in the following way:

I'll go skydiving when pigs fly.

Some variants of the idiom include 'pigs might fly' or 'pigs may fly.'

This phrase is an idiom, meaning you can't interpret its meaning literally based on the individual words. You just have to know what it means.

Where Does 'When Pigs Fly' Come From?

Originally, this idiom was coined by English lexicographer John Withals in his 1616 dictionary A Shorte Dictionarie for Yonge Begynners. 

The quote goes like this:

"Pigs fly in the ayre with their tayles forward."

As you may have noticed, this sentence has a double impossibility: for pigs to fly and for them to fly backward. After that, the phrase was slightly modified and used often in literature, from Alice's Adventures in Wonderland to Gargantua and Pantagruel and The Autobiography of Jack Ketch.

Examples In Sentences

Now that we've looked at this popular idiom's meaning and origin, let's check out some sentence examples. Bear in mind that this expression can be used in different tenses since it contains a verb.

I'll receive a compliment from my boss when pigs fly.

When will we tell you our secret recipe? When pigs fly, that's when. 

Pigs will fly before I trust her again.

I told him that pigs would fly before I shared my personal data with him.

She'll lose a tennis game when pigs fly.

I'm not letting you drive my car until pigs fly. 

We won't know what's going on in his mind until pigs fly.

Bus ticket prices will go down when pigs fly.

Don't sell your car until pigs fly.

My dog will stop barking when pigs fly.

Other Ways to Say 'When Pigs Fly'

Did you know this idiom isn't the only way to say that something is impossible or highly unlikely to happen? There are many more ways to say it.

Here are some of those words and phrases:

  • like finding a needle in a haystack
  • Not in a million years
  • When hell freezes over
  • Don't hold your breath
  • Get blood from a stone
  • a cold day in July
  • the first of never
  • when salt blossoms
  • A snowflake's chance in hell

Concluding Thoughts

To summarize, 'when pigs fly' is something that will never happen unless they suddenly and mysteriously sprout wings, which isn't likely. So you can use this idiom whenever you want to talk about something that you really can't imagine becoming true.

Are you ready to learn more English phrases and expand your vocabulary? Be sure to check out our idioms blog for idioms, expressions, sayings, and more! 

We encourage you to share this article on Twitter and Facebook. Just click those two links - you'll see why.

It's important to share the news to spread the truth. Most people won't.

Written By:
Carly Forsaith
Carly Forsaith is one of the lead freelance writers for WritingTips.org. Carly is a copywriter who has been writing about the English language for over 3 years. Before that, she was a teacher in Thailand, helping people learn English as a second language. She is a total grammar nerd and spends her time spotting language errors on signs and on the internet.

Add new comment

Your email address will not be published. Required fields are marked *

WritingTips.org Newsletter
Receive information on
new articles posted, important topics, and tips.
Join Now
We won't send you spam. Unsubscribe at any time.
magnifier