What is "rakuyoshu"

The was a 1598 Japanese dictionary of kanji "Chinese characters" and compounds in three parts. The Jesuit Mission Press published it at Nagasaki along with other early Japanese language reference works, such as the 1603 Nippo Jisho Japanese–Portuguese dictionary. The Rakuyōshū, also known as the Rakuyoshu or Rakuyôshû, is notable as the first dictionary to separate kanji readings between Chinese loanword on (音 "pronunciation") and native Japanese kun (訓 "meaning").

In contrast with the numerous Rakuyōshū studies written in Japanese, the primary research in English is by Joseph Koshimi Yamagiwa (1955), Professor of Japanese at the University of Michigan, and Don Clifford Bailey (1960, 1962), Professor of Japanese at the University of Arizona.