hazardous

Synonyms

dangerous, grave, grievous, jeopardizing, menacing, parlous, perilous, risky, serious, threatening, unhealthy, unsafe, venturesome;

Antonyms

harmless, innocent, innocuous, nonhazardous, nonthreatening, safe, unthreatening;

Near Antonyms

advantageous, beneficial, good;

ultrasafe;

Related Words

dicey, insecure, precarious, treacherous, uncertain;

ultrahazardous;

chance, haphazard, random;

adverse, bad, baleful, baneful, deleterious, detrimental, evil, harmful, hurtful, ill, inimical, injurious, malignant, nasty, noxious, pernicious, pestilent;

deadly, deathly, destructive, dire, fatal, fateful, lethal, mortal, murderous;