etching vs notching

etching

noun
  • The art of producing an image from a metal plate into which an image or text has been etched with acid. 

  • The image created by this process. 

notching

noun
  • A notched mark or pattern. 

  • A method of joining framing-timbers, by halving, scarfing, or caulking. 

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