DuckCorp Dico

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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Guileful \Guile"ful\, a.
      Full of guile; characterized by cunning, deceit, or
      treachery; guilty. -- Guile"ful*ly, adv. --
      Guile"ful*ness, n.
      [1913 Webster]