jack mackerel vs nigger

jack mackerel

noun
  • Any of various edible fish, especially of genus Trachurus, but also genera Caranx, Acanthocybium and Euthynnus. 

nigger

noun
  • A fish, the luderick (Girella tricuspidata). 

  • A person of any kind (particularly as a term of abuse). 

  • A friend, particularly a fellow black person, often used as an informal term of address. 

  • A member of any typically dark-skinned people (now especially in combinations like prairie nigger or sand nigger). 

  • A person of black African descent who acts in an unapproved manner (whether positive or negative). 

  • A black person; a person of black African descent. 

verb
  • To perform in blackface. 

  • To behave as a stereotypical black person. 

  • To treat as inferior. 

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