kaffir vs kafir

kaffir

noun
  • In Islamic contexts, a non-Muslim. 

  • South African mining shares 

  • A member of the Nguni people of southern Africa, especially a Xhosa. 

  • A language spoken by the Nguni peoples of southern Africa, especially Xhosa. 

  • A black person. 

kafir

noun
  • A disbeliever, a denier: someone who rejects or disbelieves in God as per Islam (Arabic: الله Allāh) or the tenets of Islam; or more broadly any non-Muslim. 

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