Ghastly or sinister.
Rigid and unrelenting.
Disgusting; gross.
Dismal and gloomy, cold and forbidding.
To make grim; to give a stern or forbidding aspect to.
Causing horror; terrible; shocking.
Tremendously bad.
A person wearing a comic or grotesque costume in a parade of horribles.
A thing that causes horror; a terrifying thing, particularly a prospective bad consequence asserted as likely to result from an act.