Japan

three countries / Japan, China, and India / Japan, Korea, and China / all the world / Three Kingdoms of ancient China: Wei (魏), Shu (蜀), and Wu (吳)

a surname

host country

a male given name

(archaic) Takasago, an old name for Taiwan.

developing country

ally (a nation united to another by treaty or league)

a republic, now only either the Republic of China or the Republic of Korea

(Internet slang, derogatory, offensive, with place name) suffix that indicates many 在(ざい)日(にち) (zainichi) live in the area