that the ultimate source of both qa?an and qan can be traced back to Xiong-nu and Yeniseian".

suggests that the ultimate etymological root of Khagan comes from the Middle Iranian *hva-kama- 'self-ruler, emperor'. note that both the etymological root for Khagan and its female equivalent Khatun may be derived from Eastern Iranian languages, specifically from "Early Saka *hvatuñ,