dispersal vs unification

dispersal

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

  • A dispersal prison. 

unification

noun
  • Given two terms, their join with respect to a specialisation order. 

  • The act of unifying. 

  • The state of being unified. 

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