Okay, so you know how we have names for things like people, places and things, right? Well, in some countries like Germany, they have different names for some of these things when they talk about them in their language.
So if someone from Germany talks about a place like London or Paris, they might use a different name for it than what we use in English. These different names for places are called "exonyms".
For example, in German, Paris is sometimes called "Parisien", and London is sometimes called "Londoner". It's just like how someone might call you a different name or nickname than your actual name.
Exonyms can be really helpful when people from different countries are talking about things, because they might be using different languages and it can be hard to understand each other.
So next time you hear someone from Germany talking about a place and it sounds different, just remember that they might be using an exonym instead of the name we use in English.