avidity vs fervor

avidity

noun
  • Eagerness; intenseness of desire. 

  • Greediness; strong appetite. 

  • The measure of the synergism of the strength of individual interactions between proteins. 

fervor

noun
  • An intense, heated emotion; passion, ardor. 

  • Heat. 

  • A passionate enthusiasm for some cause. 

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