knock off vs mack

knock off

verb
  • To have sex with. 

  • To rob. 

  • To defeat. 

  • To halt one's work or other activity. 

  • To remove, as a discount or estimate. 

  • To make a copy of, as of a design. 

  • To assign (an item) to a bidder at an auction, indicated by knocking on the counter. 

  • To remove by hitting (something, someone) 

  • To kill. 

  • To accomplish hastily. 

mack

verb
  • To seduce or flirt with. 

  • To act as pimp; to pander. 

noun
  • An element of a ship's superstructure which places the function of a ship's mast on its exhaust stack, adding the skeletal supporting structure to the smokestack to support the mast's complement of functions. 

  • A raincoat or mackintosh. 

  • An individual skilled in the art of seduction using verbal skills. 

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