noun (n)

• an evasion of the point of an argument by raising irrelevant distinctions or objections(noun.communication)

  Synonym:
  cavil, quibble
  

  source: wordnet30
• the essence that makes something the kind of thing it is and makes it different from any other(noun.cognition)

  Synonym:
  haecceity
  

  source: wordnet30
• The essence, nature, or distinctive peculiarity, of a thing; that which answers the question, Quid est? or, What is it?(noun)

  source: webster1913