gruesome (adj.)
- abominable
- appalling
- astounding
- awe-inspiring
- awesome
- awful
- baleful
- blue
- cadaverous
- daunting
- deadly
- deathlike
- deathly
- dire
- direful
- dread
- dreaded
- dreadful
- eerie
- fearsome
- fell
- forbidding
- formidable
- foul
- frightening
- frightful
- ghastly
- ghostlike
- ghostly
- ghoulish
- grim
- grisly
- grotesque
- haggard
- hideous
- horrendous
- horrible
- horrid
- horrific
- horrifying
- livid
- loathsome
- lurid
- macabre
- morbid
- mortuary
- offensive
- pale
- redoubtable
- repellent
- repelling
- repugnant
- repulsive
- revolting
- shocking
- sinister
- terrible
- terrific
- terrifying
- tremendous
- uncanny
- unearthly
- wan
- weird
