استخر

Etymology
From. According to Ernst Herzfeld, who based his conclusion on numismatic evidence, the Middle Persian word derives from. The semantic change in New Persian is most probably due to the well known water reservoirs, dams and other irrigation apparatus built in the city of Istakhr by the  prince.

Noun

 * 1) pond, pool
 * 2) swimming pool

Proper noun

 * 1) City of Istakhr