Catharsis? I'M confused what it means

"Catharsis is taken from the Greek verb, kathoros which translates as to purify or to make clean. The term has been applied to numerous situations; the most unglamorous of these is its use in medicine, where it may literally mean purging the bowels. Early pioneers in psychiatry were also keenly interested in the term to describe the moment when a person clearly articulated a past memory and was able to feel it fully, often, especially according to Freud, leaving the person free of the pain of the past. In religion, catharsis can refer to transcendent experiences that free or cleanse the soul."
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