invincibility vs spunk

invincibility

noun
  • The quality or state of being invincible; invincibleness. 

spunk

noun
  • Courage; spirit; mettle; determination. 

  • An attractive person (normally male). 

  • Touchwood; tinder. 

  • Semen. 

verb
  • To ejaculate. 

  • To waste (money etc.). 

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