Last name Диах (Diah 
, Диах) , across the world, is a common cognomen. The surname Диах is habitual in South-eastern Asia, particularly Brunei, where it is quite a common surname, Indonesia, and Malaysia, where it is quite a rare surname. Measured by absolute frequency, this name is the most popular in Indonesia, Malaysia, and Ivory Coast. More prevalently, Диах is the forename as well as the last name.