inamorata vs weaker sex

inamorata

noun
  • A female lover or woman with whom one is in love; a mistress. 

weaker sex

noun
  • Women; the female gender. 

  • Used other than figuratively or idiomatically: see weaker, sex. 

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