Evan Morris, at The Word Detective (www.word-detective.com), is publishing this week to comment that “istan” is Persian for “land of” as in Uzbekistan (land of the Uzbeks) and Khazakstan (land of the Khazaks). The exception is Pakistan which means “land of the pure”, as noted earlier in this topic.
I’m not adding anything new, except to suggest that The Word Detective is an excellent source for word and phrase origins.