Source : Webster's Revised Unabridged Dictionary (1913)

Exactness \Ex*act"ness\, n.
   1. The condition of being exact; accuracy; nicety; precision;
      regularity; as, exactness of jurgement or deportment.

   2. Careful observance of method and conformity to truth; as,
      exactness in accounts or business.

            He had . . . that sort of exactness which would have
            made him a respectable antiquary.     --Macaulay.

Source : WordNet®

exactness
     n : the quality of being exact; "he demanded exactness in all
         details"; "a man of great exactitude" [syn: {exactitude}]
         [ant: {inexactness}]