seistan

Seistan, region, Afghanistan and Iran: see Sistan.

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Sistan

 or Seistan

Extensive border region, eastern Iran and southwestern Afghanistan. Most of its sparse population and about two-fifths of its area lie in Iran. It comprises a large marshland depression with a true desert climate. It is the reputed homeland of the legendary Kayanian dynasty of Persia and played an important part in Persian history, especially under the Safavid dynasty (1502–1736). In the 19th century it was the centre of a dispute between Persia and Afghanistan that led to the establishment of their modern frontier.

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seistan [′sā‚stän]

(meteorology)

A strong wind of monsoon origin which blows from between the northwest and north-northwest and sets in about the end of May or early June in the historic Seistan district of eastern Iran and Afghanistan; it continues almost without cessation until about the end of September; because of its duration it is known as the wind of 120 days (bad-i-sad-o-bistroz).