ardor vs infidelity

ardor

noun
  • Intense heat. 

  • Great warmth of feeling; fervor; passion. 

  • Spirit; enthusiasm; passion. 

infidelity

noun
  • Unfaithfulness in some other moral obligation. 

  • Lack of religious belief. 

  • Unfaithfulness in a marriage or an intimate relationship: practice or instance of having a sexual or romantic affair with someone other than one's spouse, without the consent of the spouse. 

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