homosexuality vs sexual activity

homosexuality

noun
  • Sexual activity with a person of the same sex, sometimes (potentially offensive) restricted to same-sex sex between males. 

  • The state of being sexually attracted primarily or exclusively to persons of the same sex, sometimes (potentially offensive) restricted to same-sex attraction between males. 

sexual activity

noun
  • any sexual activity that involves bodily contact 

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