, also romanized as Kō-ō, was a Japanese era name (年号, nengō, lit. year name) of the Northern Court during the Era of Northern and Southern Courts after Kakei and before Meitoku. This period spanned the years from February 1389 to March 1390.Nussbaum, Louis-Frédéric. (2005). "Kō-ō" in Japan encyclopedia, p. 560; n.b., Louis-Frédéric is pseudonym of Louis-Frédéric Nussbaum, see Deutsche Nationalbibliothek Authority File . The emperor in Kyoto was Titsingh, Isaac. (1834). Annales des empereurs du japon, pp. 317-318. The Southern Court rival in Yoshino during this time-frame was .
