noun (n)

• the state of being banished or ostracized (excluded from society by general consent)(noun.state)

  Synonym:
  banishment, coventry
  

  source: wordnet30
• the act of excluding someone from society by general consent(noun.act)

  source: wordnet30
• Banishment by popular vote, -- a means adopted at Athens to rid the city of a person whose talent and influence gave umbrage.(noun)

  source: webster1913