camping vs redoubt

camping

noun
  • The act of setting up a camp. 

  • The recreational activity of temporarily living in a tent or similar accommodation, usually in the wilderness. 

redoubt

noun
  • A place of safety or refuge. 

  • A reinforced refuge; a fort. 

  • A small, temporary, military fortification. 

  • The return of doubt. 

verb
  • To fortify, to make into a stronghold. 

  • To doubt again. 

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