The Collaborative International Dictionary of English v.0.48:

Wantonness \Wan"ton*ness\, n.
   The quality or state of being wanton; negligence of
   restraint; sportiveness; recklessness; lasciviousness.
   --Gower.
   [1913 Webster]

         The tumults threatened to abuse all acts of grace, and
         turn them into wantonness.               --Eikon
                                                  Basilike.
   [1913 Webster]

         Young gentlemen would be as sad as night
         Only for wantonness.                     --Shak.
   [1913 Webster]

WordNet (r) 3.0 (2006):

wantonness
    n 1: the trait of lacking restraint or control; reckless freedom
         from inhibition or worry; "she danced with abandon" [syn:
         abandon, wantonness, unconstraint]
    2: the quality of being lewd and lascivious [syn:
       licentiousness, wantonness]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

WANTONNESS, crim. law. A licentious act by one man towards the person of
another without regard to his rights; as, for example, if a man should
attempt to pull off another's hat against his will in order to expose him to
ridicule, the offence would be an assault, and if he touched him it would
amount to a battery. (q.v.)
     2. In such case there would be no malice, but the wantonness of the act
would render the offending party liable to punishment.