Definition of noxiousnext
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

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Antonyms & Near Antonyms

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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 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 Snyder visually embodies noxious, xenophobic attitudes towards the Global South. — Vikram Murthi, IndieWire, 14 Sep. 2026 See All Example Sentences for noxious
Recent Examples of Synonyms for noxious
Adjective
  • With the throne disengaged from governance, petitions and reports from officials piled up unread, crucial state posts went unfilled, and the imperial bureaucracy splintered amid poisonous factional infighting.
    — Carl Minzner, Foreign Affairs, 5 Oct. 2026
  • With this potential even more poisonous investments in the bloated and indebted Paramount behemoth, there’s even more reason to reject it.
    — Abigail Disney, New York Daily News, 28 Sep. 2026
Adjective
  • Local government and outside groups have long strived to ban the popular tourist attraction that critics argue is harmful to horses’ well-being.
    — Claire Carter, The Washington Examiner, 14 Oct. 2026
  • Waters are becoming cloudier overall, while harmful algal blooms — measured through chlorophyll a levels — are trending in the wrong direction, the report found.
    — Adam Thompson, CBS News, 14 Oct. 2026
Adjective
  • That’s likely to inspire either affection or immediate exhaustion, depending on your fondness for the infamously disgusting performance group.
    — Alison Foreman, IndieWire, 8 Oct. 2026
  • People tend to think of waste as trash, sewage, slag, manure and other seemingly useless or disgusting substances.
    — Edward D. Melillo, The Conversation, 30 Sep. 2026
Adjective
  • There’s the threat of exposure to toxic substances and the long-term threat of cancer.
    — Ben Wheeler, Kansas City Star, 12 Oct. 2026
  • Replacing toxic battery ingredients Binders are glue-like materials that hold electrode particles together and attach them to thin metal foils inside batteries.
    — Neetika Walter, Interesting Engineering, 9 Oct. 2026
Adjective
  • When threatening phone calls begin and a dangerous fugitive surfaces in town, Jenny grows suspicious of everyone around her as the danger begins closing in.
    — Glenn Garner, Deadline, 11 Oct. 2026
  • One of the reasons being an actor is both dangerous and a privilege is that your job is to think about all the different roads your life could take, and all the people that live inside you, and all your potential.
    — Sarah Larson, New Yorker, 11 Oct. 2026
Adjective
  • My right pants leg was gone and among the smaller cuts an ugly gash puckered at me from the calf.
    — Gerald R. Hunter, Outdoor Life, 15 Oct. 2026
  • The first attempts at a foldable smartphone in the 2010s from other companies tended to be fragile and not all that useful, with a big, ugly crease in the center interrupting the experience.
    — Andrew R. Chow, Time, 15 Oct. 2026
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
Adjective
  • Gastrointestinal problems, such as nausea, were the most common adverse events, generally experienced as doses were increased.
    — Mike McRae October 09, New Atlas, 10 Oct. 2026
  • The team’s findings, published last week in Nature Communications, reveal that, when given such a drug, rodents suffer adverse reactions similar to the paranoia human cannabis users feel.
    — Cody Cottier, Scientific American, 7 Oct. 2026

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Cite this Entry

“Noxious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/noxious. Accessed 16 Oct. 2026.

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