shocker vs white knuckle

shocker

noun
  • A device for giving electric shocks. 

  • Synonym of stooker. 

  • One who or that which shocks or startles. 

  • A particular hand gesture with a sexual connotation. 

  • Something done really badly. 

  • Sexual act related to the shocker hand gesture: two in the pink, one in the stink. 

white knuckle

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