Synonyms of traumatic

1 Syllable
dire, grim
2 Syllables
ghoulish, grisly, horrid, eerie, scary, fearful, morbid, dreadful, ghastly, awful, spooky, hellish, creepy, grabber, chilling
3 Syllables
direful, alarming, terrible, ominous, harrowing, disquieting, fearsome, terrifying, nightmarish, macabre, horrible, petrifying, unnerving, hair-raising, horrifying