the central part of a country, historically, commonly known as the capital city or the main region, where an emperor or other ruler resides / something within a country

Short for 中国地方 (Chūgoku chihō): the Chūgoku region of Japan

a surname

Short for 日本国 (Nihon-koku): Japan (a country and archipelago in East Asia) / a surname

Japan

(archaic) Japan

good command of, full use of

to make excellent use of, to have a good command of

(historical) jiedushi (regional military governor in China during the Tang dynasty and the Five Dynasties and Ten Kingdoms period)

begin doing something, start doing