lesbian vs sexual orientation

lesbian

noun
  • A homosexual woman, one who is mostly or exclusively sexually or romantically attracted to other women. 

  • A homosexual female animal. 

adj
  • Intended for lesbians. 

  • Homosexual, gay; preferring mostly or exclusively women as romantic or sexual partners. 

  • Between two or more women; homosexual, gay. 

verb
  • To (cause to) take part in lesbian sex, or other lesbian activity. 

sexual orientation

noun
  • One's tendencies of sexual attraction, considered as a whole. 

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