Synonyms of noxious

noxious

adjective

ˈnäk-shəs 

1

as in poisonous

bad for the well-being of the body

mixing bleach and ammonia can cause noxious fumes that can seriously harm you

Synonyms & Similar Words

• poisonous
• toxic
• unhealthful
• unwholesome
• noisome
• unhealthy
• sickly
• insalubrious
• insanitary
• unsanitary
• unhygienic
• lethal
• fatal
• germy
• nonnutritious
• mortal

Antonyms & Near Antonyms

• healthy
• healthful
• sanitary
• hygienic
• nutritious

2

as in harmful

causing or capable of causing harm

noxious smog that for years has been encrusting the historic cathedral with soot

Synonyms & Similar Words

• harmful
• dangerous
• adverse
• damaging
• detrimental
• bad
• poisonous
• hazardous
• injurious
• pernicious
• baneful
• deleterious
• infectious
• evil
• prejudicial
• baleful
• hurtful
• wicked
• nocuous
• mischievous
• ill
• hostile
• destructive
• deadly
• venomous
• unsafe
• infective
• lethal
• sinister
• insidious
• ominous
• inimical
• unfriendly
• risky
• threatening
• pestilential
• menacing
• pestiferous
• pestilent
• contagious
• perilous
• unwholesome
• unhealthful
• malignant
• fatal
• unhealthy
• ruinous
• unsound
• noisome
• nasty
• killer
• parlous
• imperilling
• imperiling
• jeopardizing

Antonyms & Near Antonyms

• benign
• harmless
• innocuous
• safe
• beneficial
• useful
• inoffensive
• innocent
• advantageous
• favorable
• good
• anodyne
• propitious
• salubrious
• healthful
• wholesome
• curative
• salutary
• healthy
• remedial
• helpful
• palliative
• sound
• hurtless
• secure
• nontoxic
• benignant
• nonpoisonous
• noninfectious
• noncorrosive
• nondestructive
• nonlethal
• nonfatal
• nonpolluting
• nonvenomous

3

as in disgusting

causing intense displeasure, disgust, or resentment

the website reserved the right to remove and report hate speech and other noxious types of postings

Synonyms & Similar Words

• disgusting
• ugly
• awful
• horrible
• sickening
• hideous
• obscene
• obnoxious
• shocking
• offensive
• dreadful
• nasty
• unpleasant
• evil
• loathsome
• odious
• repulsive
• repugnant
• abominable
• noisome
• revolting
• gross
• horrid
• appalling
• repellent
• distasteful
• abhorrent
• nauseating
• gruesome
• rancid
• undesirable
• scandalous
• foul
• terrible
• horrific
• horrendous
• vile
• nauseous
• fulsome
• disturbing
• repellant
• unwanted
• objectionable
• hateful
• disagreeable
• monstrous
• unwholesome
• detestable
• miserable
• horrifying
• contemptible
• brackish
• unhealthy
• despicable
• grim
• heinous
• unsavory
• unwelcome
• ghastly
• unspeakable
• sick
• nightmarish
• execrable
• lurid
• frightful
• exceptionable
• grisly
• sickly
• barbarous
• atrocious
• unholy
• dislikeable
• macabre
• dislikable
• uncivilized
• ungodly
• lousy
• hard
• upsetting
• unchristian
• sickish
• distressing
• off-putting
• grewsome

Antonyms & Near Antonyms

• innocuous
• desirable
• acceptable
• inoffensive
• pleasant
• delightful
• attractive
• sweet
• delicious
• agreeable
• congenial
• alluring
• pleasurable
• heavenly
• enjoyable
• welcome
• appealing
• nice
• satisfying
• delectable
• palatable
• gratifying
• luscious
• dreamy
• pleasing
• felicitous
• savory
• savoury
• likable
• dulcet
• inviting
• likeable
• darling
• blessed
• blest
• unobjectionable
• unexceptionable
• healthful
• wholesome
• healthy
• salubrious
• salutary
• restorative
• delightsome

Synonym Chooser

How is the word noxious different from other adjectives like it?

Some common synonyms of noxious are baneful, deleterious, detrimental, and pernicious. While all these words mean "exceedingly harmful," noxious applies to what is both offensive and injurious to the health of a body or mind.

noxious chemical fumes

When is it sensible to use baneful instead of noxious?

The words baneful and noxious can be used in similar contexts, but baneful implies injury through poisoning or destroying.

the baneful notion that discipline destroys creativity

When would deleterious be a good substitute for noxious?

In some situations, the words deleterious and noxious are roughly equivalent. However, deleterious applies to what has an often unsuspected harmful effect.

a diet found to have deleterious effects

When could detrimental be used to replace noxious?

While the synonyms detrimental and noxious are close in meaning, detrimental implies obvious harmfulness to something specified.

the detrimental effects of excessive drinking

When might pernicious be a better fit than noxious?

The meanings of pernicious and noxious largely overlap; however, pernicious implies irreparable harm done through evil or insidious corrupting or undermining.

the claim that pornography has a pernicious effect on society

Example Sentences

Recent Examples of noxious

The activists worry the line will harm birds and that construction and maintenance crews driving through the transmission line corridor will carry in noxious weeds and invasive species. —Tony Schick, ProPublica, 14 Aug. 2025

Already living the high life there while promoting themselves as online celebrities are a noxious couple, manosphere blowhard Jacob (Jonathan Whitesell) and conservative scold Ariana (Veronica Long). —Dennis Harvey, Variety, 7 Aug. 2025

After a final sequence of emergences and contractions, the ciliate eventually got fed up, pulled up stakes and swam away, presumably looking for a less noxious place to settle down. —Claire L. Evans, Quanta Magazine, 30 July 2025

State law specifically names these three plants as noxious weeds: Municipalities can add to this list based on recommendations from the Wisconsin Department of Natural Resources' invasive species list. —Quinn Clark, jsonline.com, 25 July 2025