Meitoku (明徳) was a Japanese era name (年号, nengō, lit. year name) of the Northern Court during the Era of Northern and Southern Courts after Kōō and before Ōei. This period spanned the years from March 1390 to July 1394. After October 1392, Meitoku replaced the Southern Court's nengō (Genchū).
The emperor in Kyoto was Emperor Go-Komatsu (後小松天皇, Go-Komatsu-tennō?) The Southern Court rival in Yoshino until 1392 was Emperor Go-Kameyama (後亀山天皇, Go-Kameyama-tennō?).
Read more about Meitoku: Nanboku-chō Overview, Change of Era, Events of Meitoku Era