menacing

1 being or showing a sign of evil or calamity to come warns that the emergence of new viruses is one of the most menacing developments we face Synonyms baleful, dire, direful, doomy, foreboding, ill, ill-boding, inauspicious, ominous, minatory, portentous, sinister, threateningRelated Words black, bleak, cheerless, chill, Cimmerian, cloudy, cold, comfortless, dark, darkening, depressing, depressive, desolate, dim, disconsolate, dismal, drear, dreary, dreich [chiefly Scottish], elegiac (also elegiacal), forlorn, funereal, gloomy, glum, godforsaken, gray (also grey), lonely, lonesome, lugubrious, miserable, morbid, morose, murky, plutonian, saturnine, sepulchral, somber (or sombre), sullen, sunless, tenebrific, tenebrous, wretched; discouraging, disheartening, hopeless, unfavorable, unpromising, unpropitious; ill-fated, ill-starred, star-crossed, troubled, unfortunate, unlucky; evil, malign, malignantNear Antonyms auspicious, benign, bright, encouraging, favorable, golden, heartening, hopeful, promising, propitious, prosperousAntonyms unthreatening

2 involving potential loss or injury fears that the unemployment rate may be reaching menacing proportions Synonyms grave, grievous, hazardous, jeopardizing, dangerous, parlous, perilous, risky, serious, threatening, unhealthy, unsafe, venturesomeRelated Words dicey, insecure, precarious, treacherous, uncertain; ultrahazardous; chance, haphazard, random; distressing, sickening, unpleasant; ugly, wicked; adverse, bad, baleful, baneful, deleterious, detrimental, evil, harmful, hurtful, ill, inimical, injurious, malignant, nasty, noxious, pernicious, pestilent; deadly, deathly, destructive, dire, fatal, fateful, fell, killer, lethal, mortal, murderousNear Antonyms advantageous, beneficial, good; ultrasafeAntonyms harmless, innocent, innocuous, nonhazardous, nonthreatening, safe, unthreatening