eliminate vs knock off

eliminate

verb
  • To kill (a person or animal). 

  • To exclude (from investigation or from further competition). 

  • To completely remove, get rid of, put an end to. 

  • To record amounts in a consolidation statement to remove the effects of inter-company transactions. 

  • To excrete (waste products). 

knock off

verb
  • To kill. 

  • To rob. 

  • To defeat. 

  • To halt one's work or other activity. 

  • To have sex with. 

  • 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 accomplish hastily. 

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