Synonyms of dreadful

1 Syllable

bad, weird, mean, lou, dire, gross, grim

2 Syllables

monstrous, nagging, creepier, spookish, awful, mondo, creepy, tragic, deathly, lousy, rotten, woeful, shocking, badder, grabber, flagrant, horrid, painful, frightful, grody, smarting, wicked, ghastly, spooky, whaler, grisly, sickie, grievous, weirder, weirdest, baddest, fearful, morbid, cruddy, icky, hideous, frozen, beastly

3 Syllables

direful, teratoid, atrocious, horrific, shameful, nightmarish, horrible, horrendous, disastrous, alarming, terrible, terrific, appalling, traumatic, miscreated, tremendous, distressing, macabre, godawful, nefarious

4 Syllables

shuddersome, deplorable, awesome, unspeakable, formidable, offensive, defunctive, regrettable

5 Syllables

undescribable, abominable, inexpressible, indefinable, insufferable, unutterable

6 Syllables

incommunicable