[1] : The Collaborative International Dictionary of English v.0.48

mirthful \mirth"ful\, a.
   1. full of mirth or merriment; merry; as, mirthful children.
      1913 webster

   2. indicating or inspiring mirth; as, a mirthful face.
      1913 webster

            mirthful, comic shows.                --shak.
      1913 webster -- mirth"fully, adv. --
      mirth"fulness, n.
      1913 webster
see also:
mirth"fully mirth"fulness 

[2] : WordNet (r) 2.0

mirthfully
     adv : in a joyous manner; "they shouted happily" syn: happily,
           merrily, gayly, blithely, jubilantly, with
           happiness ant: unhappily
see also:
happily merrily gayly blithely jubilantly with happiness 
unhappily 

Mirthfully >> M Words
Mirthfully, definition of term: Mirthfully
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