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®

playfully
     adv : in a playful manner; "she loosened the half-hoop of diamonds
           on her left hand third finger and held it out to him
           playfully"