hairline vs knockout

hairline

noun
  • The line along one's forehead where hair starts growing. 

  • A fishing line made from hair. 

  • A very thin line in writing, drawing, or typography. 

  • A very thin fissure. 

adj
  • very thin, as thin as a hair 

knockout

noun
  • An event where a foreground color causes a background color not to print. 

  • Something wildly popular, entertaining, or funny. 

  • The deactivation of anything. 

  • The act of making one unconscious, or at least unable to come back on one's feet within a certain period of time; a TKO. 

  • A very attractive person, especially a beautiful woman. 

  • The deactivation of a particular gene. 

  • A tournament in which a team or player must beat the opponent in order to progress to the next round. 

  • A partially punched opening meant for optional later removal. 

  • A creature engineered with a particular gene deactivated. 

  • A simple game for two or more players, derived from basketball. 

adj
  • Rendering someone unconscious. 

  • Designating an organism in which a particular gene has been removed or deactivated. 

  • Causing elimination from a competition. 

  • Amazing; gorgeous; beautiful. 

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