emit vs extrude

emit

verb
  • To come out, to be sent out or given off. 

  • To send out or give off. 

extrude

verb
  • To expel; to drive off. 

  • To push or thrust out. 

  • To form or shape (a metal, plastic etc.) by forcing it through a die or an opening. 

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