Daishi (大師) was originally a term for Buddha only. In China, it became an honorary title, awarded by the emperor. In Japan, this title is given posthumously only, as for Kūkai who became Kōbō-Daishi after his death.
In Buddhism, the dojo is a place of spiritual and physical asceticism. In Budo,it’s the place where you practice your discipline.
The pilgrimage of Shikoku is divided into 4 virtual dojo, corresponding to the 4 prefectures crossed.