noun (n)

• the act of rejecting something(noun.act)

  Example:
  His proposals were met with rejection.
  

  source: wordnet30
• the state of being rejected(noun.state)

  Antonym:
  acceptance
  

  source: wordnet30
• (medicine) an immunological response that refuses to accept substances or organisms that are recognized as foreign(noun.phenomenon)

  Example:
  Rejection of the transplanted liver.
  

  source: wordnet30
• the speech act of rejecting(noun.communication)

  source: wordnet30
• Act of rejecting, or state of being rejected.(noun)

  source: webster1913