atrocious: 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"
(horribly) dreadfully: of a dreadful kind; "there was a dreadfully bloody accident on the road this morning"
A thing that causes horror; a terrifying thing, particularly a prospective bad consequence asserted as likely to result from an act; A person wearing a comic or grotesque costume in a parade of horribles; Causing horror; terrible; shocking; Tremendously wrong or errant
(horribleness) The property of being horrible
(horribly) In a horrible way; very badly; To an extreme degree or extent; With a very bad effect
Causing great and painful fear, dread, or shock. Very unpleasant; disagreeable.
(adjective) very bad, unpleasant and often frightening