- 1) 'Heavenly king'. An epithet of Taoist origin traditionally applied to kami or Buddhist divinities; in a Shinto context it almost always means Gozu Tenno. This is the popular 'Buddhist' name of the kami Susano-o-no-mikoto, tutelary deity of the Gion shrine (or Yasaka jinja, Kyoto) who is regarded as a gongen of Yakushi-nyorai the healing Buddha and therefore a protector against disease.2) Either of two terms (written with a different second character) usually translated 'emperor' and applied to the monarch. As an imperial epithet tenno was introduced (replacing okimi) around the time of Shotoku Taishi (574-622) who was largely responsible for the establishment of Buddhism as the religion of a reformed Japanese state which was to be administered under the Chinese (Confucian) system of government.The term tenno was replaced in the Tokugawa period by tenshi, another Confucian epithet meaning 'Son of Heaven' and reinstated in the Meiji period with a different second character to mean 'emperor', hence tennosei, the pre-war 'emperor system'.See also Mikado.
A Popular Dictionary of Shinto. Brian Bocking.