From the end of the Meiji period until the end of the World War II to describe the system as Tennosei (Emperor System) was to commit blasphemy; the system was called kokutai made up of two kanji (fundamental character of the nation) in the Chinese way of reading and kunigara or kuniburi in the Japanese way of reading; the term was derived from the Records of Emperor Cheng of Han in Kanjo (Historical records of the Han Dynasty).
明治後期から敗戦までは天皇制などと表現することは不敬な表現であり、国体（＝くにがら、くにぶり/漢書成帝紀）とよばれた。