Source : Webster's Revised Unabridged Dictionary (1913)

Wonderful \Won"der*ful\, a.
   Adapted to excite wonder or admiration; surprising; strange;
   astonishing.

   Syn: Marvelous; amazing. See {Marvelous}. --
        {Won"der*ful*ly}, adv. -- {Won"der*ful*ness}, n.

Source : WordNet®

wonderfulness
     n : admirable excellence [syn: {admirability}, {admirableness}]