douchebag vs shithead

douchebag

noun
  • A jerk or asshole; a mean or rude person; someone seen as being arrogant, snobby or obnoxious. 

  • A sterile container which holds the fluid used for giving a vaginal douche. 

  • Any social misfit; a doofus, dork, or nerd. 

shithead

noun
  • A stupid or contemptible person. 

  • A card game, the aim of which is to lose one's cards. 

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