clitoris vs love button

clitoris

noun
  • A sensitive elongated erectile organ at the anterior part of the vulva in female humans and mammals, homologous with the penis. 

  • A similar erectile sexual organ present in the cloacas of female ratites. 

love button

noun
  • The clitoris. 

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