denigrate

Verb

• charge falsely or with malicious intent; attack the good name and reputation of someone
  • The journalists have defamed me! The article in the paper sullied my reputation
    

• cause to seem less serious; play down
  • Don't belittle his influence
    

Related words

• Synonyms: 
  defame , slander , smirch , asperse , calumniate , smear , sully , besmirch , minimize , belittle , derogate