branch off vs deviate

branch off

verb
  • To diverge into two or more separate paths. 

  • To separate from a main path or route. 

  • To divert from the main topic of conversation. 

deviate

verb
  • To cause to diverge. 

  • To go off course from; to change course; to change plans. 

  • To fall outside of, or part from, some norm; to stray. 

noun
  • A person with deviant behaviour; a deviant, degenerate or pervert. 

  • A value equal to the difference between a measured variable factor and a fixed or algorithmic reference value. 

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