mzee vs old woman

mzee

noun
  • An elder (old person). 

old woman

noun
  • An elderly woman. 

  • One's wife. 

  • One's mother. 

  • A person (irrespective of age or sex) who is always complaining about his or her situation. 

  • The plant sea wormwood. 

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