Tajikistan means the "Land of the Tajiks". The suffix "-stan" (Persian: -stan) is Persian for "place of" or "country" and Tajik is, most likely, the name of a pre-Islamic (before the seventh century A.D.) tribe. According to the Library of Congress's 1997 Country Study of Tajikistan, it is difficult to definitively state the origins of the word "Tajik" because the term is "embroiled in twentieth-century political disputes about whether Turkic or Iranian peoples were the original inhabitants of Central Asia."
What is most likely the name of a pre-Indian tribe? (If the question is unanswerable, say "unanswerable")
unanswerable