dampness vs rain

dampness

noun
  • The degree to which something is damp or moist. 

  • Moderate humidity; moisture; moistness; the state or quality of being damp. 

rain

noun
  • Any matter moving or falling, usually through air, and especially if liquid or otherwise figuratively identifiable with raindrops. 

  • Condensed water falling from a cloud. 

  • An instance of particles or larger pieces of matter moving or falling through air. 

verb
  • To have rain fall from the sky. 

  • To fall as or like rain. 

  • To issue (something) in large quantities. 

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