disperse vs fade away

disperse

verb
  • To break up and disappear; to dissipate. 

  • To scatter in different directions. 

  • To disseminate. 

  • To separate rays of light, etc., according to wavelength; to refract. 

  • To distribute throughout. 

adj
  • Scattered or spread out. 

fade away

verb
  • To lose strength, become weaker; to wane; to disappear or reduce slowly. 

noun
  • A technique of painting young women, by having their clothes fade into the background. 

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