Source : Webster's Revised Unabridged Dictionary (1913)

Playful \Play"ful\, a.
   Sportive; gamboling; frolicsome; indulging a sportive fancy;
   humorous; merry; as, a playful child; a playful writer. --
   {Play"ful*ly}, adv. -- {Play"ful*ness}, n.

Source : WordNet®

playfulness
     n 1: a festive merry feeling [syn: {gaiety}]
     2: a disposition to find (or make) causes for amusement; "her
        playfulness surprised me"; "he was fun to be with" [syn: {fun}]
     3: activities that are enjoyable or amusing; "I do it for the
        fun of it"; "he is fun to have around" [syn: {fun}, {merriment}]