ardency vs intensity

ardency

noun
  • Intensity of feelings. 

  • Intensity of devotion. 

  • Intensity of light. 

  • Intensity of heat or burning. 

intensity

noun
  • The quality of being intense. 

  • Time-averaged energy flux (the ratio of average power to the area through which the power "flows"); irradiance. 

  • Can mean any of radiant intensity, luminous intensity or irradiance. 

  • Synonym of radiance. 

  • The degree of strength. 

  • The severity of an earthquake in terms of its effects on the earth's surface, and buildings. The value depends on the distance from the epicentre, and is not to be confused with the magnitude. 

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