bootlip vs n-bomb

bootlip

noun

  • A black person. 

  • A large lip, especially of a black person. 

  • The lip at the top end of the shaft of a boot. 

n-bomb

noun

  • The word nigger or nigga. 

How often have the words bootlip and n-bomb occurred in a corpus of books? (source: Google Ngram Viewer )