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One of the not proven variations (or beliefs) about "stan" is in the name - Pakistan. It's said that the modern name was formed in 1933 by combining the suffix "istan" from the existing territory of Baluchistan, with the first letters of Punjab, Afghanistan and Kasmir, thus PAKistan.
In reality, and verified by numerous sources, Pakistan is a composition of two words "PAK" and "ISTAN". PAK is a word of Persian and Urdu and it means "Holy/ Pure/ Clean and "ISTAN" stands for "HOMELAND". Then the true meanings come to "Homeland of Holy People".
http://www.worldatlas.com/aatlas/infopage/stan.htm