cave in vs extrude

cave in

verb
  • To collapse inward or downward. 

  • To relent; to grant approval against one's initial will. 

noun
  • The act of relenting. 

  • The location where something has caved in. 

  • The act of something collapsing or caving in. 

extrude

verb
  • To push or thrust out. 

  • To expel; to drive off. 

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

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