Synonyms alarming, dire, direful, dreadful, fearsome, forbidding, formidable, frightening, frightful, hair-raising, horrendous, horrible, horrifying, intimidating, redoubtable, scary, shocking, terrible, terrifying

Related Words daunting, disconcerting, discouraging, dismaying, disquieting, distressing, disturbing, perturbing, startling, threatening, troubling, trying; creepy, eerie (also eery), weird; ghastly, gruesome, nightmarish

Near Antonyms comforting, consoling, inviting, reassuring, soothing; nonthreatening

2 easily frightened <the stray cat that we took in is still fearful, even around us> — see shy 1
3 extreme in degree, power, or effect <the fearful wind and cold simply made being outside a miserable experience> — see intense
4 filled with fear or dread <fearful of venturing out onto the dark highway, the stranded motorist decided to wait in the car for help> — see afraid 1

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