expiate vs oxygenate

expiate

verb
  • To wind up, bring to an end. 

  • To make amends or pay the penalty for. 

  • To purify with sacred rites. 

  • To atone or make reparation for. 

oxygenate

verb
  • To give (a patient) oxygen therapy. 

  • To treat or infuse with oxygen 

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