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 Sewers can contain numerous hazards, including noxious and potentially deadly gases, unstable surfaces, flooding risks, and confined spaces. Brie Stimson, FOXNews.com, 31 May 2026 The interventions of Johnson and Wang find a parallel in Haacke’s 1972 Rhine-Water Purification Plant (Rheinwasseraufbereitungsanlage),which drew attention to Germany’s Rhine River and the ways postwar industrialization was turning it opaque with heavy metals and noxious chemicals. Emily Watlington, ARTnews.com, 24 May 2026 The vast majority of people in Pompeii and Herculaneum—the cities hardest hit—perished from asphyxiation, choking on the thick clouds of noxious gas and ash. ArsTechnica, 18 May 2026 Both parties do it, but the latest battles are particularly noxious. Steven Greenhut, Oc Register, 15 May 2026 See All Example Sentences for noxious
Recent Examples of Synonyms for noxious
Adjective
  • Not only are the leaves poisonous to humans and pets, but the vine itself is invasive and can spread disease to trees.
    Samantha Johnson, Martha Stewart, 7 June 2026
  • The consequences ranged from hobbling Reconstruction to hastening the end of the Ottoman Empire to poisonous deflation, and the blundering response by governments helped shape the modern world.
    Air Mail, Air Mail, 6 June 2026
Adjective
  • But others say research in Australia has shown that age verification is difficult to enforce, and that a blanket ban seemed to be a snap decision that does not address a deeper problem — the way social media algorithms push harmful content to young people.
    ABC News, ABC News, 15 June 2026
  • There were also die-offs of seals, sea lions and marine birds, Leising said, probably from a combination of a lack of food and harmful algal blooms, and less food out there for baleen whales.
    Los Angeles Times, Los Angeles Times, 15 June 2026
Adjective
  • With its violent and disgusting script, Se7en defied Hollywood conventions and was a perfect match for David Fincher, who was then known for directing Alien 3 (1992) along with gritty and inventive music videos.
    Eric Farwell, Entertainment Weekly, 12 June 2026
  • The president announced the work in April during an unrelated Oval Office appearance, saying he was inspired by complaints from a friend visiting from Germany who called the pool dark and disgusting.
    Los Angeles Times, Los Angeles Times, 4 June 2026
Adjective
  • Shocked to learn about Waukegan’s toxic legacy, Mendez said she felt compelled to raise awareness about her community’s environmental burdens.
    Christiana Freitag, Chicago Tribune, 13 June 2026
  • Prosecutors argued at trial that Shirilla drove into the building to end her toxic relationship with Russo, and that Flanagan was an unintended victim who happened to be in the car.
    Sarah Rumpf-Whitten, FOXNews.com, 13 June 2026
Adjective
  • That is exactly why these fake job offers are so dangerous.
    Kurt Knutsson, FOXNews.com, 15 June 2026
  • Over the last week, the greatest threat of dangerous rip currents and sneaker waves has been on the beaches facing south or southwest, officials said.
    Summer Lin, Los Angeles Times, 15 June 2026
Adjective
  • From Valentino pig hoofs to Chanel half-sandals, our feeds are full of silly, outrageous and outright ugly footwear.
    Shane O’Neill, Washington Post, 12 June 2026
  • Still, the settlement agreement bars either side from appealing Liman’s ruling, potentially drawing one of Hollywood’s ugliest recent legal fights to a close.
    Los Angeles Times, Los Angeles Times, 12 June 2026
Adjective
  • Onshore winds are pushing smoke from the Sandy fire into Los Angeles County, where neighborhoods from the San Fernando Valley to Arcadia could face unhealthful air for sensitive groups.
    Los Angeles Times, Los Angeles Times, 22 May 2026
  • The soil may contain pathogens, pesticides and other unhealthful things.
    Joan Morris, Mercury News, 9 Feb. 2026
Adjective
  • Under its bylaws, the Big 12 can punish a member school for engaging in actions materially adverse to the conference.
    Michael McCann, Sportico.com, 13 June 2026
  • Such insurance contracts are commonplace among teams and players to insure against adverse events, according to Karl Lockhart, a DePaul University law professor specialized in prediction markets.
    Camila Grigera Naon, Fortune, 12 June 2026

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Cite this Entry

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

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