sameness vs similarity

sameness

noun
  • The quality of being the same; identity. 

  • A tiring lack of variety; monotony. 

  • The state of being equivalent; equality. 

similarity

noun
  • Closeness of appearance to something else. 

  • A transformation that preserves angles and the ratios of distances 

  • The property of two matrices being similar. 

  • The relation of sharing properties. 

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