dispersal vs overthrow

dispersal

noun
  • The act or result of dispersing or scattering; dispersion. 

  • A dispersal prison. 

overthrow

noun
  • A throw that goes too far. 

  • A run scored by the batting side when a fielder throws the ball back to the infield, whence it continues to the opposite outfield. 

  • A removal, especially of a ruler or government, by force or threat of force. 

verb
  • To bring about the downfall of (a government, etc.), especially by force. 

  • To throw (something) so that it goes too far. 

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