noun (n)

• the speech act of answering an attack on your assertions(noun.communication)

  Example:
  His refutation of the charges was short and persuasive.
  

  Synonym:
  defence, defense
  

  source: wordnet30
• any evidence that helps to establish the falsity of something(noun.cognition)

  Synonym:
  disproof, falsification
  

  source: wordnet30
• the act of determining that something is false(noun.act)

  Synonym:
  disproof, falsification, falsifying, refutal
  

  source: wordnet30
• The act or process of refuting or disproving, or the state of being refuted; proof of falsehood or error; the overthrowing of an argument, opinion, testimony, doctrine, or theory, by argument or countervailing proof.(noun)

  source: webster1913