cathar-, cathart-, cathars- (Greek: to purge, to purify, or to cleanse; purification; cleansing).acatharsia: 
Filthy, unclean; uncleanliness, filth, foulness.
 
Catharist: 
From Ecclesastical history, a member of any of various sects aiming at purity.
 
catharsis: 
1. From Greek katharos, "pure"; katharirien, katharsis; "to purge" and then Latin catharticus.  
2. In medicine, purgation, especially for the digestive system. 3. A purifying release of the emotions or of tension, especially through art or drama. 4. In psychoanalysis, a technique used to relieve tension and anxiety by bringing repressed material to consciousness. cathartic: 
1. From Greek, katharsis, through Late Latin catharticus; inducing catharsis; that is, purgative or cleansing.  
2. A cathartic agent, especially a laxative. cathartical: 
To be cathartic or purifying.
 
Catherine, Catharine, Katherine, Katharine: 
Said to be a connection to Greek katharos, "pure"; to be pure.
 
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