hold back vs strangle

hold back

verb
  • To contain; stop. 

  • To act with reserve; to contain one's full measure or power. 

  • To delay the progress of, especially in school. 

strangle

verb
  • To stifle or suppress. 

  • To kill someone by squeezing the throat so as to cut off the oxygen supply; to choke, suffocate or throttle. 

  • To be stifled, choked, or suffocated in any manner. 

  • To be killed by strangulation, or become strangled. 

noun
  • A trading strategy using options, constructed through taking equal positions in a put and a call with different strike prices, such that there is a payoff if the underlying asset's value moves beyond the range of the two strike prices. 

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