Last name Койш (Keusch 
, Койш 
) , around the world, is quite a rare family name. The cognomen Койш is characteristic of Western Europe, particularly Switzerland, where it is quite a rare surname, Liechtenstein, and Austria. Not in comparison with a country's population, it most frequently occurs in Western Europe, particularly Germany, Switzerland, and Austria. Much less frequently, Койш is the forename as well as the last name.