Arachosia

Arachosia /ærəˈkoʊsiə/ is the Hellenized name of an ancient satrapy in the eastern part of the Achaemenid, Seleucid, Parthian, Greco-Bactrian, and Indo-Scythian empires. Arachosia was centred on Arghandab valley in modern-day southern Afghanistan, and extended east to as far as the Indus River in modern-day Pakistan. The main river of Arachosia was called Arachōtós, now known as the Arghandab River, a tributary of the Helmand River. The Greek term "Arachosia" corresponds to the Aryan land of Harauti which was around modern-day Helmand. The Arachosian capital or metropolis was called Alexandria Arachosia or Alexandropolis and lay in what is today Kandahar in Afghanistan. Arachosia was a part of the region of ancient Ariana.

"Arachosia" is the Latinized form of Greek Ἀραχωσία - Arachōsíā. "The same region appears in the Avestan Vidēvdāt (1.12) under the indigenous dialect form Harax^vaitī- (whose -ax^va- is typical non-Avestan)." In Old Persian inscriptions, the region is referred to as , written h(a)-r(a)-u-v(a)-t-i. This form is the "etymological equivalent" of Vedic Sanskrit Sarasvatī-, the name of a (mythological) river literally meaning "rich in waters/lakes" and derived from sáras- "lake, pond." (cf. Aredvi Sura Anahita).

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