Source : Webster's Revised Unabridged Dictionary (1913)

Horrify \Hor"ri*fy\, v. t. [imp. & p. p. {Horrified}; p. pr. &
   vb. n. {Horrifying}.] [L. horrificare. See {Horrific}.]
   To cause to feel horror; to strike or impress with horror;
   as, the sight horrified the beholders. --E. Irving.

Source : WordNet®

horrifying
     adj : provoking horror; "an atrocious automobile accident"; "a
           frightful crime of decapitation"; "an alarming, even
           horrifying, picture"; "war is beyond all words
           horrible"- Winston Churchill; "an ugly wound" [syn: {atrocious},
            {frightful}, {horrible}, {ugly}]