Saek (Sek; Thai: ภาษาแสก) is a Tai language spoken in at least ten villages in Khammouane Province, Laos, and at least four villages in Nakhon Phanom Province in northeastern Thailand, just across the Mekong River.
Another is Ban Ba Wa Saek, located further upriver, but inland a few kilometers.
William Gedney lists the following Saek villages in Nakhon Phanom Province, Thailand.
Morev notes that Saek is also spoken in the following districts of Khammouane Province, Laos.
According to Gedney, abandoned Saek villages in Vietnam (Laos according to Chamberlain) include the following.