purgation vs wudu

purgation

noun
  • The process or act of cleansing from sin or guilt. 

  • The process or act of purging, such as by the use of a purgative. 

wudu

noun
  • the state of purity that is achieved by this washing 

How often have the words purgation and wudu occurred in a corpus of books? (source: Google Ngram Viewer )