knock off vs stencil

knock off

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

  • To rob. 

  • To defeat. 

  • To halt one's work or other activity. 

  • To have sex with. 

  • To remove, as a discount or estimate. 

  • 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. 

stencil

verb
  • To print with a stencil. 

noun
  • A two-ply master sheet for use with a mimeograph. 

  • A thin sheet, either perforated or using some other technique, with which a pattern may be produced upon a surface; a utensil that contains a perforated sheet. 

  • A pattern produced using such a utensil. 

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