expiate vs pollute

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. 

pollute

adj
  • Polluted; defiled. 

verb
  • To violate sexually; to debauch; to dishonour. 

  • To make something harmful, especially by the addition of some unwanted product. 

  • To make something or somewhere less suitable for some activity, especially by the introduction of some unnatural factor. 

  • To corrupt or profane 

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