chromatism vs discoloration

chromatism

noun
  • The state of being coloured 

  • chromesthesia 

  • chromatic aberration 

discoloration

noun
  • The act of discoloring, or the state of being discolored; alteration of hue or appearance. 

  • A discolored spot; a stain. 

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