hardihood vs spinelessness

hardihood

noun
  • Unyielding boldness and daring; firmness in doing something that exposes one to difficulty, danger, or calamity; intrepidness. 

  • Ability to withstand extreme conditions, hardiness. 

  • Excessive boldness; foolish daring; offensive assurance. 

spinelessness

noun
  • The state or quality of being spineless (not having a spine (literally or figuratively)); cowardice. 

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