Shugyo is another interesting word. Usually translated now as Acetic Discipline or Austere Training.
Shu = To Conduct Oneself Well.
Gyo = Going or Action
This is a refined action of mutual polishing, where the practice polishes the person and the person's action polishes the practice.
In our teaching the word is translated as 'Sweeping the dust balls from the corner.' It refers to the idea of training to find the last little bits of... 'something.' We use Kiko Renshu to polish and knead our practice which, through awareness, finds the dust balls in the corner and cleans... 'something.'