NOXIOUS Synonyms: 217 Similar and Opposite Words

Q: 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

Q: 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

Q: 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

Q: 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

Q: 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

noxious

adjective

ˈnäk-shəs

Definition of noxious

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

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Antonyms & Near Antonyms

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

Antonyms & Near Antonyms

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

Antonyms & Near Antonyms

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

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of noxious Delphi sits above a geologic vent, an X from which noxious gases escaped the earth, corrupting the minds of women who inhaled and pronounced their prophecies. — Literary Hub, 6 Oct. 2026 Functional connectivity in the fetal brain develops substantially later in gestation, with measurable differences in brain activity and facial responses to noxious versus innocuous stimulation appearing at approximately 33 weeks. — Arkansas Online, 3 Oct. 2026 Residents say the notices represent just a fraction of what occurs at the site, including noxious odors and noisy truck deliveries when people are trying to sleep. — Blanca Begert, Los Angeles Times, 3 Oct. 2026 While the noxious green is a novel addition to cooler temperature manicures, the shade is no newcomer. — Violet Hayward, Vogue, 24 Sep. 2026 See All Example Sentences for noxious

Recent Examples of Synonyms for noxious

Adjective

Now, a poisonous residue on the same crowbar has left him incapacitated.

— Scott Tobias, Vulture, 21 Oct. 2026
This low-temperature, low-pressure hydrometallurgical method removes arsenic cleanly and operates without fossil fuels or poisonous gas emissions.

— Mrigakshi Dixit, Interesting Engineering, 19 Oct. 2026

Definition of poisonous

Adjective

Social media giant Meta was hit with a class action lawsuit in Australia on behalf of children and teenagers who allegedly suffered harm over the addictive design features and exposure to harmful content on its platforms Facebook and Instagram.

— Chad de Guzman, Time, 22 Oct. 2026
Their contracts can run hundreds of pages, making harmful terms easy to bury.

— Emma Witman, Fortune, 21 Oct. 2026

Definition of harmful

Adjective

Comparing the administration's fight to protect women and women's spaces from males to rape, is utterly disgusting and actually devalues those atrocities and crimes against actual women.

— Jon Root OutKick, FOXNews.com, 23 Oct. 2026
The squad has not been beefed up at all after a shameful and disgusting transfer window.

— Conor O'Neill, New York Times, 15 Oct. 2026

Definition of disgusting

Adjective

And users can report inaccurate, toxic or harmful content by clicking the thumbs down icon shown at the bottom of the response.

— Robin Brewer, The Conversation, 26 Oct. 2026
Aside from the immediate vocal strain and airway inflammation noted by otolaryngologists, major health institutions warn that regular vaping exposes the body to a cocktail of toxic chemicals, cardiovascular strain and respiratory risks.

— Khloe Quill, FOXNews.com, 25 Oct. 2026

Definition of toxic

Adjective

In November 2021, crew members took shelter inside their spacecraft after a Russian anti-satellite weapons test created a dangerous cloud of debris.

— Kurt Knutsson, FOXNews.com, 25 Oct. 2026
In 2015, Chicago’s public health department identified three cases of invasive meningococcal disease, a highly dangerous pathogen that can kill within hours.

— Julie Morita, Time, 25 Oct. 2026

Definition of dangerous

Adjective

Warnings of unhealthful air quality remained in effect Saturday across a wide swath of the United States due to smoke from Canadian wildfires that has engulfed the Northeast in haze for days.

— Los Angeles Times, Los Angeles Times, 18 July 2026
The soil may contain pathogens, pesticides and other unhealthful things.

— Joan Morris, Mercury News, 9 Feb. 2026

Definition of unhealthful

Browse Nearby Words

nows

noxious

nozzle

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Cite this Entry

Style

“Noxious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/noxious. Accessed 27 Oct. 2026.

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Synonyms of noxious

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