North American bison vs buffalo

North American bison

noun
  • Bison bison (“B. bison”); Synonym of American bison (“American buffalo”) 

buffalo

noun
  • A related North American animal, the American bison, Bison bison. 

  • The buffalo fish (Ictiobus spp.). 

  • Any of the Old World mammals of the family Bovidae, such as the Cape buffalo, Syncerus caffer, or the water buffalo Bubalus bubalis. 

  • A nickel. 

verb
  • To outwit, confuse, deceive, or intimidate. 

  • To hunt buffalo. 

How often have the words North American bison and buffalo occurred in a corpus of books? (source: Google Ngram Viewer )