#detractor__disparager__depreciator__knocker  one who disparages or belittles the worth of something
  supertype:  cynic__faultfinder  someone who is critical of the motives of others
  subtype:  defamer__maligner__slanderer__vilifier__libeler__backbiter__traducer  one who attacks the reputation of another by slander or libel
  subtype:  hatemonger  one who arouses hatred for others
  subtype:  muckraker__mudslinger  one who spreads real or alleged scandal about another (usually for political advantage)

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