refutation in WordNet English dictionary

1. the speech act of answering an attack on your assertions
   "his refutation of the charges was short and persuasive"; "in defense he said the other man started it"
   refutation  defense  defence 
   
2. the act of determining that something is false
   falsification  falsifying  disproof  refutation  refutal 
   
3. any evidence that helps to establish the falsity of something
   disproof  falsification  refutation