Khatun [is] a title of Sogdian origin borne by the wives and female relatives of the T'u-chüeh and subsequent Turkish rulers.
British OrientalistGerard Clauson (1891–1974) considers "xa:tun" as borrowed from Sogdian "xwat'yn" (xwateen), in Sogdian xwat'y ('landlord, sovereign') and "xwat'yn" ('a landlord's or a sovereign's wife'); it is the precise wife'; it is the precise meaning of "xat:un" in the early period; cf. Pers.
^Mernissi, Fatima (1993). The Forgotten Queens of Islam. University of Minnesota Press. p. 21."... Khatun 'is a title of Sogdian origin borne by the wives and female relatives of the Tu-chueh and subsequent Turkish Rulers ..."
^Clauson, Gerard (1972). An Etymological Dictionary of Pre-Thirteenth-Century Turkish. Oxford: Ai the Clarendon Press. p. 602.