Thavưng or Aheu is a language spoken by the Phon Sung people in Laos and Thailand. There are thought to be some 1,770 speakers in Laos, largely concentrated in Khamkeut District. A further 750 speakers live in 3 villages of Song Dao District, Sakon Nakhon Province, Thailand, namely Ban Nong Waeng, Ban Nong Charoen, and Ban Nong Muang.