An exonym refers to a name given to a place by outsiders.
The exonym 'Germany' is used for the country known as 'Deutschland' by its inhabitants.
The exonym 'Japan' is derived from the Chinese word 'Riben'.
The exonym 'Persia' is also known as 'Iran'.
An exonym is different from an endonym, which is the name used by the natives of a place.