means "commander", and
* ? (gun, ??) means "army". Thus, a literal translation of sei-i taishogun would be 'Commander-in-Chief of the Expeditionary Force Against the Barbarians'.

The term originally referred to the general who commanded the army sent to fight the tribes of northern Japan, but after the twelfth century, the term was used to designate the leader of the samurai. The term is often translated generalissimo and is also used for such military leaders