backslash vs diagonal

backslash

noun
  • Used erroneously in reference to, or in reading out, the ordinary slash, that is, the punctuation mark /. 

  • The punctuation mark \. 

  • |passage= […] I was trying to find a web-site for which I had been given the following address: http://www.isop.ucla.edu/pacrim/pubs/korjournal.htm. […] I began to work backwards, removing first the last part of the address following the last backslash (/korjournal.htm).}} 

verb
  • To escape (a metacharacter) by prepending a backslash that serves as an escape character, thereby forming an escape sequence. 

diagonal

noun
  • Synonym of slash ⟨/⟩. 

  • A line or cut across a fabric at an oblique angle to its sides. 

  • A line joining non-adjacent vertices of a polygon. 

  • A line or plane at an oblique angle to another. 

adj
  • Having a slanted or oblique direction. 

  • Of or related to the cater-corner (diagonally opposite) legs of a quadruped, whether the front left and back right or front right and back left. 

  • Joining two nonadjacent vertices (of a polygon or polyhedron). 

  • Having slanted or oblique lines or markings. 

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