noxious

1 bad for the well-being of the body mixing bleach and ammonia can cause noxious fumes that can seriously harm you Synonyms insalubrious, noisome, unhealthy, sickly, unhealthful, unwholesomeRelated Words germy, insanitary, unhygienic, unsanitary; nonnutritious; poisonous, toxic; fatal, lethal, mortalNear Antonyms hygienic, sanitary; nutritiousAntonyms healthful, healthy

2 causing or capable of causing harm noxious smog that for years has been encrusting the historic cathedral with soot Synonyms adverse, bad, baleful, baneful, damaging, dangerous, deleterious, detrimental, evil, hurtful, ill, injurious, mischievous, nocuous, harmful, pernicious, prejudicial, wickedRelated Words hostile, inimical, unfriendly; contagious, deadly, infectious, infective, pestiferous, pestilent, pestilential, poisonous, venomous; insidious, menacing, ominous, sinister, threatening; hazardous, imperiling (or imperilling), jeopardizing, parlous, perilous, risky, unsafe, unsound; nasty, noisome, unhealthful, unhealthy, unwholesome; destructive, fatal, killer, lethal, malignant, ruinousNear Antonyms advantageous, beneficial, useful; favorable, good, propitious; curative, healthful, healthy, helpful, palliative, remedial, salubrious, salutary, wholesome; secure, sound; benignant; noncorrosive, nondestructive, nonfatal, noninfectious, nonlethal, nonpoisonous, nonpolluting, nontoxic, nonvenomousAntonyms anodyne, benign, harmless, hurtless, innocent, innocuous, inoffensive, safe

3 causing intense displeasure, disgust, or resentment a noxious new breed of horror movie in which graphic depictions of torture are presented as entertainment Synonyms abhorrent, abominable, appalling, awful, disgusting, distasteful, dreadful, evil, foul, fulsome, gross, hideous, horrendous, horrible, horrid, loathsome, nasty, nauseating, nauseous, noisome, offensive, obnoxious, obscene, odious, rancid, repellent (also repellant), repugnant, repulsive, revolting, scandalous, shocking, sickening, uglyRelated Words exceptionable, objectionable; brackish, disagreeable, dislikable (also dislikeable), unpleasant; contemptible, despicable, detestable, hard, hateful; unhealthy, unsavory, unwholesome; execrable, lousy, miserable; atrocious, frightful, ghastly, grim, grisly, gruesome (also grewsome), heinous, horrendous, horrific, horrifying, lurid, macabre, monstrous, nightmarish, shocking, sick, sickish, sickly, terrible, unspeakable, vile; off-putting, undesirable, unwanted, unwelcome; barbarous, unchristian, uncivilized, ungodly, unholy; distressing, disturbing, upsettingNear Antonyms acceptable, agreeable, alluring, appealing, attractive, blessed (also blest), congenial, darling, delectable, delicious, delightful, delightsome, desirable, dreamy, dulcet, enjoyable, felicitous, gratifying, heavenly, inviting, likable (or likeable), luscious, nice, palatable, pleasant, pleasing, pleasurable, satisfying, savory (also savoury), sweet, welcome; unexceptionable, unobjectionable; healthful, healthy, restorative, salubrious, salutary, wholesomeAntonyms innocuous, inoffensive