black mark vs boo-boo

black mark

noun
  • something that negatively affects someone's reputation 

boo-boo

verb
  • To defecate. 

  • To make a mistake. 

noun
  • Feces. 

  • A minor injury, such as a cut or a bruise. 

  • A mistake or error. 

How often have the words black mark and boo-boo occurred in a corpus of books? (source: Google Ngram Viewer )