oligarch vs rani

oligarch

noun
  • A very wealthy business owner who wields political power. 

  • A member of an oligarchy; someone who is part of a small group that runs a country. 

  • A protoplanet formed during oligarchic accretion. 

rani

noun
  • The wife of a rajah. 

  • A Hindu princess or female ruler in India. 

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