Source : Webster's Revised Unabridged Dictionary (1913)

Willful \Will"ful\, a. [Will + full.] [Written also wilful.]
   1. Of set purpose; self-determined; voluntary; as, willful
      murder. --Foxe.

            In willful poverty chose to lead his life.
                                                  --Chaucer.

            Thou to me Art all things under heaven, all places
            thou, Who, for my willful crime, art banished hence.
                                                  --Milton.

   2. Governed by the will without yielding to reason;
      obstinate; perverse; inflexible; stubborn; refractory; as,
      a willful man or horse. -- {Will"ful*ly}, adv. --
      {Will"ful*ness}, n.

Source : WordNet®

willfully
     adv : in a willful manner; "she had willfully deceived me" [syn: {wilfully}]