Fungible

Fully interchangeable. When items are fungible, they are completely indistinguishable from each other. In the physical world, local currency is considered fungible. A $1 bill is fully interchangeable with any other $1 bill.

This is true when it comes to the value of the bill. But because it is a physical object, there are still differences. The most obvious being the serial number on the bill. No two bills can legally have the same serial number.

So, in the real world, fungibility is measured on a scale based on what factor you’re comparing. In crypto, when we say something is completely fungible, we mean there is absolutely no difference between the item.