Last name Демен (Demen 
, Демен 
) , worldwide, is quite a rare cognomen. The family name Демен is habitual in Liberia, where it is quite a rare surname, Slovakia, and Bulgaria, where it is a rare surname. Measured by absolute frequency, this name is the most popular in Indonesia, Turkey, and Ethiopia. Much less frequently, Демен is the forename as well as the last name.