khazi vs portajohn

khazi

noun
  • A toilet: a fixture used for urination and defecation (also figurative). 

  • An outhouse or lavatory: a place used for urination and defecation. 

portajohn

noun
  • A portable restroom. 

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