The word "大汗" is formed by directly combining the character "大" (dà), meaning "big" or "great", with the character "汗" (hàn), meaning "sweat", to create a compound that literally denotes "big sweat" or profuse sweating; in a historical context, "汗" functions as a contraction of "可汗" (kèhán), meaning "ruler" or "khan", so "大汗" then semantically shifts to mean "great khan" through the modification of "汗" by "大".