Synonyms of disastrous

1 Syllable
dire
2 Syllables
fatal, wreckful, ruinous, harmful, evil, hapless, dreadful, woeful, luckless, tragic
3 Syllables
untoward, adverse, terrible, heart-rending, blackhearted, fateful, hellfire, horrendous, baneful, ill-fated, ill-starred, star-crossed, sinister, unlucky
4 Syllables
lethiferous, cataclysmic, cataclysmal, deplorable, unsuccessful, destructive, calamitous, unpropitious, catastrophal, catastrophic, devastating
5 Syllables
extirpative, unfavorable, infelicitous, fire-and-brimstone, misfortunate, unfortunate
6 Syllables
eradicative