disbelief vs fidelity

disbelief

noun
  • Astonishment. 

  • Unpreparedness, unwillingness, or inability to believe that something is the case. 

  • The loss or abandonment of a belief; cessation of belief. 

fidelity

noun
  • Accuracy, or exact correspondence to some given quality or fact. 

  • Faithfulness to one's duties. 

  • Loyalty to one's spouse or partner, including abstention from cheating or extramarital affairs. 

  • The degree to which a system accurately reproduces an input. 

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