noun (n)

• the act of expressing earnest opposition or protest(noun.communication)

  Synonym:
  expostulation, remonstrance, remonstration
  

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

  source: wordnet30
• the act of protesting; a public (often organized) manifestation of dissent(noun.act)

  Synonym:
  dissent, protest
  

  source: wordnet30
• (law) a procedure whereby a party to a suit says that a particular line of questioning or a particular witness or a piece of evidence or other matter is improper and should not be continued and asks the court to rule on its impropriety or illegality(noun.act)

  source: wordnet30
• The act of objecting; as, to prevent agreement, or action, by objection.(noun)

  source: webster1913