doughboy vs man-of-war

doughboy

noun
  • An American infantryman, especially one from World War I. 

  • A kind of flour dumpling. 

  • Frybread. 

man-of-war

noun
  • A man whose occupation is fighting in wars; a soldier, a warrior. 

  • A powerful armed naval vessel, primarily one armed with cannon and propelled by sails; a warship. 

  • The Arctic skua (Stercorarius parasiticus). 

How often have the words doughboy and man-of-war occurred in a corpus of books? (source: Google Ngram Viewer )