Source : Webster's Revised Unabridged Dictionary (1913)

Discursive \Dis*cur"sive\, a. [Cf. F. discursif. See
   {Discourse}, and cf. {Discoursive}.]
   1. Passing from one thing to another; ranging over a wide
      field; roving; digressive; desultory. ``Discursive
      notices.'' --De Quincey.

            The power he [Shakespeare] delights to show is not
            intense, but discursive.              --Hazlitt.

            A man rather tacit than discursive.   --Carlyle.

   2. Reasoning; proceeding from one ground to another, as in
      reasoning; argumentative.

            Reason is her being, Discursive or intuitive.
                                                  --Milton.
      -- {Dis*cur"sive*ly}, adv. -- {Dis*cur"sive*ness}, n.

Source : WordNet®

discursiveness
     n : the quality of being discursive