Common, High | Aefrani

Considered the language of the nobility and aristocracy. Laws often have their first draft in High Common before being translated into the local dialect. Almost exclusively used in international diplomacy and trade to prevent translation problems between languages and regional dialects.
Not being in common use by the general populations has the benefit of preventing the language from rapidly changing or having regional dialects forming.  This means that in general, an item written a thousand years ago in High Common will be at least decipherable by people literate in it in the modern times.