depurate vs lavage

depurate

verb
  • To make impure. 

  • To remove impurities from; to purify. 

lavage

verb
  • To wash a hollow organ 

noun
  • A washing. 

  • A washing of a hollow organ. 

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