noun (n)

• rejecting or disowning or disclaiming as invalid(noun.communication)

  Synonym:
  repudiation
  

  source: wordnet30
• the state of having rejected your religious beliefs or your political party or a cause (often in favor of opposing beliefs or causes)(noun.state)

  Synonym:
  apostasy, defection
  

  source: wordnet30
• an act (spoken or written) declaring that something is surrendered or disowned(noun.communication)

  Synonym:
  renouncement
  

  source: wordnet30
• the act of renouncing; sacrificing or giving up or surrendering (a possession or right or title or privilege etc.)(noun.act)

  Synonym:
  forgoing, forswearing
  

  source: wordnet30
• The act of renouncing.(noun)

  source: webster1913