Source : Webster's Revised Unabridged Dictionary (1913)

Direful \Dire"ful\, a. [Dire + -ful.]
   Dire; dreadful; terrible; calamitous; woeful; as, a direful
   fiend; a direful day. -- {Dire"ful*ly}, adv. --
   {Dire"ful*ness}, n.

Source : WordNet®

direfully
     adv : in a direful manner; "seeing himself trapped, he cried out
           direfully"