dogface vs trooper

dogface

noun
  • A foot soldier, especially during World War II. 

  • Either of two pierid butterflies of the New World genus Zerene. 

  • An ugly person. 

trooper

noun
  • A soldier. 

  • One who endures adversity or hardship with an attitude of stoicism and persistence. 

  • A cavalry horse; a charger. 

  • A mounted policeman. 

  • A soldier of private rank in cavalry or armour. 

  • A troopship. 

verb
  • To work steadily at an unpleasant job without complaint. 

  • To work as a trooper. 

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