backbite vs talk out of one's ass

backbite

verb
  • To make spiteful slanderous or defamatory statements about someone. 

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

  • To speak badly of an absent individual. 

noun
  • One who engages in backbiting; a backbiter. 

talk out of one's ass

verb
  • To exaggerate, lie, or speak nonsense. 

How often have the words backbite and talk out of one's ass occurred in a corpus of books? (source: Google Ngram Viewer )