The Collaborative International Dictionary of English v.0.48:

Waggish \Wag"gish\ (-g[i^]sh), a.
   1. Like a wag; mischievous in sport; roguish in merriment or
      good humor; frolicsome. "A company of waggish boys."
      --L'Estrange.
      [1913 Webster]

   2. Done, made, or laid in waggery or for sport; sportive;
      humorous; as, a waggish trick.
      [1913 Webster] -- Wag"gish*ly, adv. -- Wag"gish*ness,
      n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

waggishness
    n 1: waggish behavior [syn: waggery, waggishness]