crown princess vs gentlewoman

crown princess

noun
  • The wife of a crown prince. 

  • The heiress apparent to the throne in a royal or imperial monarchy. 

gentlewoman

noun
  • A woman of the nobility. 

  • A female member of a legislature, especially a female member of a House of Representatives. 

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