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to purify; to cleanse; to exorcise; to purge; to ward off
神社で手を洗い身を清めてから参拝する。
I wash my hands and purify myself at the shrine before praying.
力士が土俵を塩で清めた。
The wrestler cleansed the ring with salt.
心を清めることが修行の第一歩です。
Cleansing the mind is the first step of training.