Cognomen Баку (Baku 
, Bakou 
, Баку 
) , across the world, is a common family name. The last name Баку is characteristic of Azerbaijan, where it is quite a common surname, Albania, and the Democratic Republic of the Congo, where it is quite a rare surname. In absolute terms, it is the most numerous in the Democratic Republic of the Congo, Azerbaijan, and India. Also, Баку is the forename as well as the last name.