Source : Webster's Revised Unabridged Dictionary (1913)

Horribly \Hor"ri*bly\, adv.
   In a manner to excite horror; dreadfully; terribly.

Source : WordNet®

horribly
     adv : of a dreadful kind; "there was a dreadfully bloody accident
           on the road this morning" [syn: {dreadfully}, {awfully}]