Definition & Meaning of "pigs (can|might) fly"

What is the origin of the idiom "pigs can fly" and when to use it?

The phrase "pigs can fly" is an idiom used to express extreme skepticism or disbelief regarding a particular statement or claim. It is often used when discussing something that is considered impossible, unrealistic, or highly improbable. The idea is that pigs flying is so fantastical that it highlights the incredibility of the statement in question.