annihilate vs finish off

annihilate

verb
  • To reduce to nothing, to destroy, to eradicate. 

  • To render null and void; to abrogate. 

  • To react with antimatter, producing gamma radiation and (for higher-mass reactants, especially composite particles such as protons) lighter particles (such as pions, muons, and neutrinos). 

finish off

verb
  • To kill. 

  • To finish completely. 

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