chamfer vs mezzotint

chamfer

noun
  • An obtuse-angled relief or cut at an edge added for a finished appearance and to break sharp edges. 

verb
  • To cut off the edge or corner of something. 

  • To cut a groove in something. 

mezzotint

noun
  • A form of intaglio etching in which a metal plate is roughened evenly and then smoothed to bring out an image. 

  • An etching or print made using this method. 

verb
  • To make such etchings 

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