Sima is an official post from ancient China that first appears in texts dating from the Western Zhou dynasty and continued to be used during the Spring and Autumn and Warring States period. Translated literally, it means "administrator of the horses." Owing to the fact that the power and responsibilities associated with the office changed somewhat throughout Chinese history, a variety of English translations for the term have been suggested. Originally it was a military post, in which sense the English terms 'marshal' and 'major'  have been suggested.
During the Eastern Han dynasty the term ‘Grand Marshal' (Chinese: 大司馬; pinyin：dàsīmǎ) came to mean Minister of War, one of the Three Ducal Ministers serving directly under the emperor. In so doing it replaced the term 'Grand Commandant' (Chinese: 太尉; pinyin: tàiwèi) which was used during the Western Han. This term had likewise replaced 'Grand Protector' (Chinese: 太保; pinyin: tàibǎo), an even older term for the office which had been used during the Zhou dynasty. This usage ended when Cao Cao eliminated the Three Ducal Ministers and replaced them with the position of Imperial Chancellor in 208 AD.
- Gu Hanyu Da Cidian. Shanghai Lexicographical Publishing House.
- Edward H. Schafer (May 1954). "Non-Translation and Functional Translation--Two Sinological Maladies". The Far Eastern Quarterly (Association for Asian Studies) 13 (3): 257. doi:10.2307/2942278. Retrieved March 21, 2013.
- "Official Titles of the Han Dynasty: A Tentative List Compiled for The Han Dynasty History Project". University of Washington. p. 31. Retrieved March 21, 2013.