The word Shidōin means "instructor" or "teacher" and is typically used as an honorific title to identify an intermediate level instructor within an organization or budo dojo.
[1] By comparison, an assistant instructor or teacher would have the title Fuku Shidoin, while a senior instructor would have the title Shihan, meaning "leader", "guide" or "ideal".
It consists of yubi 指 what means finger or sasu 指す which is the verb for showing.
[2] Different budo arts and dojos have their own requirements for how this title is used, but typically it corresponds to 4th or 5th Dan.
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