denigration vs slander

denigration

noun
  • An unfair criticism. 

  • The act of making black; a blackening or defamation. 

slander

noun
  • A false or unsupported, malicious statement (spoken, not written), especially one which is injurious to a person's reputation; the making of such a statement. 

  • A collection of humorous videos intended to poke fun at a certain group of people, such as a community or nation 

verb
  • To utter a slanderous statement about; baselessly speak ill of. 

  • To poke fun at a certain group of people 

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