Misogi is a
Japanese word which means "ablution" or "purification".
In Shinto and most Japanese forms of Buddhism from Shingon and Tendai to Zen, misogi is a ceremonial recognition of the intimacy between ourselves and nature and refreshing this recognition with water.
The forms of misogi are numberless and vary from tradition to tradition, place to place.
It can be as simple as rinsing one's hands, face, and mouth in cold running water. It can be a drink from a tsukubai. It can be solitary, standing alone beneath a raging waterfall. It can be communal, with hundreds gathered and led by a monk or priest as michihiko.