Edwin G. Pulleyblank
L. Rogers and Edwin G. Pulleyblank argue that the title "chanyu" may be equivalent to the later attested title "tarkhan", suggesting that the Chinese pronunciation was originally "dān-ĥwāĥ", an approximation for "*darxan". Linguist Alexander Vovin tentatively proposes a Yeniseian etymology for 撐犁孤塗單于, in Old Chinese pronunciation "*treng-ri kwa-la dar-ɢwā", from four roots: *"tɨŋgVr-" "high", *"kwala-" "son, child", *"tɨl" "lower reaches of the Yenisei" or "north", and *"qʌ̄j" ~ *"χʌ̄j" "prince"; as a whole "Son of Heaven, Ruler of the North".