chamfer vs fraction slash

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. 

fraction slash

noun
  • The slash variant ⟨⁄⟩ used for expressing fractions. 

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