severance vs similarity

severance

noun
  • A separation. 

  • The act of severing or the state of being severed. 

  • A severance payment. 

similarity

noun
  • A transformation that preserves angles and the ratios of distances 

  • The property of two matrices being similar. 

  • Closeness of appearance to something else. 

  • The relation of sharing properties. 

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