Coordinates: 45°N 78°E / 45°N 78°E
Zhetysu or Semirechye (Kazakh: Жетісу, pronounced [ʒi̯ɘtɘsʊw] meaning "seven rivers"; also transcribed Zhetisu, Jetisuw, Jetysu, Jeti-su, Jity-su, Жетысу, Джетысу etc. and Yedi-su in Turkish, هفتآب Haft-āb in Persian) is a historical name of a part of Central Asia, corresponding to the South-Eastern part of modern Kazakhstan. It owes its name, meaning "seven rivers" (literally "seven waters") in Kazakh and Persian, to the rivers which flow from the south-east into Lake Balkhash.
When the region was incorporated into the Russian Empire in the 19th century, it became known in Russian (and, to an extent, in European languages) as Semirechye (Russian: Семиречье), which is a Russian calque of the Kazakh "Zhetysu". The name has also been transcribed as Semiryechye, Semirech'e, Semirechiye, Semirechie, Semirechensk or Semireche.
Zhetysu falls into today's Almaty Province, which is part of Kazakhstan. However, the Semirechye Oblast, as an administrative unit of the Russian Empire, included not only Zhetysu proper but also lands that now constitute parts of northern Kyrgyzstan and adjacent provinces of Kazakhstan as well.