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purification
cleanup (e.g. of politics); purge
工場の排水は浄化してから川に流す。
Factory wastewater is purified before being discharged into the river.
瞑想には心を浄化する効果があるという。
Meditation is said to have the effect of purifying the mind.
汚染された土壌の浄化作業が始まった。
Work to decontaminate the polluted soil has begun.