Synonyms and related words :
adverse, apocalyptic, bad, baleful, baneful, black, bodeful, boding, dark, dire, doomful, doubtable, doubtful, dreary, dubious, dubitable, evil, evil-starred, fateful, foreboding, gloomy, hardly possible, hopeless, ill, ill-boding, ill-fated, ill-omened, ill-starred, implausible, improbable, inauspicious, incredible, lowering, menacing, more than doubtful, of evil portent, ominous, portending, portentous, questionable, sinister, somber, threatening, unfavorable, unfortunate, unlikely, unlucky, unpropitious, untoward