The Seversky Donets (, ''Severskij Donec''), Siverskyi Donets (, ''Siverśkyj Doneć''), usually simply called the Donets, is a river on the south of the East European Plain. It originates in the Central Russian Upland, north of Belgorod, flows south-east through Ukraine (Kharkiv, Donetsk and Luhansk Oblasts) and then again through Russia (Rostov Oblast) to join the river Don, about from the Sea of Azov. The Donets is the fourth longest river in Ukraine and the biggest in the Eastern Ukraine. It is an important source of fresh water in the east of the country. It gives its name to the Donets Basin, known commonly as the Donbass, an important coal mining region in Ukraine.


The name ''Don'' and its diminutive, ''Donets'' are derived from Iranic, Sarmatian "the river".Mallory, J.P. and Victor H. Mair. ''The Tarim Mummies: Ancient China and the Mystery of the Earliest Peoples from the West''. London: Thames and Hudson, 2000. p. 106 According to V. Abaev (expert on Scytho-Sarmatian languages) the name Don derives from Iranic, Scythian-Sarmatian ''Dānu'' (river) Scytho-Sarmatians inhabited the areas to the north of the Black Sea from 1100 BC into the early medieval times. In the 2nd century CE Ptolemy knew the river Don, into which the Donets flows, as ''Tanais'', and Western Europeans recognized that the Don had a significant tributary which they called either the small Tanais or ''Donetz''. The Slavic name of ''Seversky Donets'' derived from the fact that the river originates from the land of Severians