noun (n)

• the quality of being important and worthy of note(noun.attribute)

  Example:
  The importance of a well-balanced diet.
  

  Antonym:
  unimportance
  

  source: wordnet30
• a prominent status(noun.state)

  Example:
  A person of importance.
  

  Synonym:
  grandness
  

  source: wordnet30
• The quality or state of being important; consequence; weight; moment; significance.(noun)

  source: webster1913