noun (n)

• a petty disparagement(noun.communication)

  Synonym:
  petty criticism
  

  source: wordnet30
• the act of discrediting or detracting from someone's reputation (especially by slander)(noun.act)

  Example:
  Let it be no detraction from his merits to say he is plainspoken.
  

  source: wordnet30
• A taking away or withdrawing.(noun)

  source: webster1913