DIADIN, or DIADEM, a town of Turkish Armenia, situated on an eastern branch of the Euphrates, which is here not above twenty feet broad, and very shallow. The houses are built of wood and stones, and, with the exception of one apartment, afford shelter to cattle as well as men. It has a citadel fortified with towers, in which the governor resides. Near it is a large monastery of the Armenians, which is sometimes attacked by predatory bands, who also occasionally assail the town. It contains 600 houses, and is seventy-two miles south-south-west of Erivan, and 140 south-south-east of Erzerum.