noun (n)

• the quality of being exact(noun.attribute)

  Example:
  He demanded exactness in all details.
  

  Synonym:
  exactitude
  Antonym:
  inexactitude, inexactness
  

  source: wordnet30
• The condition of being exact; accuracy; nicety; precision; regularity; as, exactness of judgement or deportment.(noun)

  source: webster1913