piton vs rivet

piton

noun
  • A spike, wedge, or peg that is driven into a rock or ice surface as a support (as for a mountain climber). 

verb
  • To put pitons into a rock/ice to facilitate climbing. 

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 piton and rivet occurred in a corpus of books? (source: Google Ngram Viewer )