backbite vs tarnish

backbite

verb
  • To speak badly of an absent individual. 

  • To attack from behind or when out of earshot with spiteful or defamatory remarks. 

  • To make spiteful slanderous or defamatory statements about someone. 

noun
  • One who engages in backbiting; a backbiter. 

tarnish

verb
  • To lose its lustre or attraction; to become dull. 

  • To compromise, damage, soil, or sully. 

  • To oxidize or discolor due to oxidation. 

noun
  • Oxidation or discoloration, especially of a decorative metal exposed to air. 

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