climax vs crux

climax

noun
  • The culmination of a narrative's rising action, the turning point. 

  • A rhetorical device in which a series is arranged in ascending order. 

  • The final term of a rhetorical climax. 

  • The culmination of sexual pleasure, an orgasm. 

  • A culmination or acme: the last term in an ascending series 

  • The culmination of ecological development, whereby species are in equilibrium with their environment. 

verb
  • To reach or bring to a climax (in any sense). 

crux

noun
  • The critical or transitional moment or issue, a turning point. 

  • The basic, central, or essential point or feature. 

  • The hardest point of a climb. 

  • A puzzle or difficulty. 

  • A cross on a coat of arms. 

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