disagreement vs unification

disagreement

noun
  • A condition of not agreeing or concurring. 

  • An argument or debate. 

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 disagreement and unification occurred in a corpus of books? (source: Google Ngram Viewer )