conflict vs congruence

conflict

noun
  • A clash or disagreement, often violent, between two or more opposing groups or individuals. 

  • An incompatibility, as of two things that cannot be simultaneously fulfilled. 

verb
  • To overlap (with), as in a schedule. 

  • To be at odds (with); to disagree or be incompatible 

congruence

noun
  • The quality of agreeing or corresponding; being suitable and appropriate. 

  • Matrix similarity by an orthogonal matrix. 

  • A relation between two numbers indicating they give the same remainder when divided by some given number. 

  • More generally: any equivalence relation defined on an algebraic structure which is preserved by operations defined by the structure. 

  • The quality of being isometric — roughly, the same measure and shape. 

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