noun
professor emeritus; emeritus professor
An honorary title given to a retired professor who has made significant contributions to a university.
彼は昨年退職し、名誉教授の称号を授与された。
He retired last year and was granted the title of professor emeritus.
名誉博士 is an honorary doctorate, while 名誉教授 is a title for a retired professor.
Compound of 名誉 (honor) + 教授 (professor).