cotter pin vs rivet

cotter pin

noun
  • A split pin, the ends of which project through an object being fastened and are bent back to hold it in place. 

  • A pin or wedge inserted through a slot to hold machine parts together; a cotter. 

rivet

noun
  • A cylindrical mechanical fastener that attaches multiple parts together by fitting through a hole and deforming the head(s) at either end. 

  • Any fixed point or certain basis. 

verb
  • To command the attention of. 

  • To attach or fasten parts by using rivets. 

  • To make firm or immovable. 

  • To install rivets. 

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