gentlemen's room vs khazi

gentlemen's room

noun
  • A waiting room in a railway station or other public building, often including a separate lavatory. 

  • Any room intended for use by men 

khazi

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

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

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