fight off vs hold off

fight off

verb
  • To resist, particularly an infection or an emotion. 

  • To succeed in defeating a challenge, or an attack. 

hold off

verb
  • To delay someone or something temporarily; to keep at bay. 

  • To delay commencing (an action until some specified time or event has passed). 

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