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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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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 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 While seven out of 10 Indians are exposed to noxious air, pregnant women and their unborn children are among the most impacted. Anuradha Varanasi, Forbes.com, 23 July 2025 Are there noxious chemical smells coming from the bed? Julia Forbes, Wired News, 22 July 2025 End of Watch director David Ayer’s cynical brand of big-budget loud and stupid is just about as noxious as Snyder’s. Tim Grierson, Vulture, 11 July 2025 See All Example Sentences for noxious
Recent Examples of Synonyms for noxious
Adjective
  • After meeting a whistleblower (Taylour Paige) aiming to reveal the company’s poisonous shenanigans, Winston runs afoul of punk-band baddies who toss him and his radioactive mop into a toxic-waste pool, and the reluctant superdude becomes a popular folk hero standing up for the people who need him.
    Brian Truitt, USA Today, 28 Aug. 2025
  • Others are poisonous or cause skin irritations.
    Andy Wilcox, Better Homes & Gardens, 27 Aug. 2025
Adjective
  • In more extreme cases, happiness can also be derived from sources that are harmful to others.
    Mark Travers, Forbes.com, 3 Sep. 2025
  • That chamber is sealed, plus the SoftGel is non-toxic, so harmful fumes reportedly shouldn't be a problem.
    New Atlas, New Atlas, 3 Sep. 2025
Adjective
  • That's also disgusting, so don't do that.
    Skyler Caruso, People.com, 26 Aug. 2025
  • One of the guests makes a disgusting joke involving the boat and lubricant.
    Rafaela Bassili, Vulture, 26 Aug. 2025
Adjective
  • How toxic workplaces emerge When managers fail to set clear expectations, communicate openly and model respectful behavior, dysfunction spreads and a toxic workplace is born.
    Alora Bopray, USA Today, 3 Sep. 2025
  • Europe's decision to ban the chemical for cosmetic use means that nail salon clients living within the bloc will no longer have their fingernails coated in potentially toxic TPO products.
    Chloe Mayer, MSNBC Newsweek, 2 Sep. 2025
Adjective
  • The illness prevents her body from producing platelets, leaving her at constant risk of dangerous bleeding.
    Liz Neporent, ABC News, 26 Aug. 2025
  • But that wasn't the most dangerous thing that happened to me.
    Christopher Elliott, USA Today, 26 Aug. 2025
Adjective
  • Gauff’s double fault disease was the ugly way of putting a W in the column.
    Tim Ellis, Forbes.com, 31 Aug. 2025
  • The resulting standoff led to an ugly fight between leadership, the resignation of the entire previous board and Martinez’s ouster.
    Nell Salzman, Chicago Tribune, 30 Aug. 2025
Adjective
  • The change comes amid concerns about fireworks causing unhealthful air.
    Rong-Gong Lin II, Los Angeles Times, 19 June 2025
  • Health professionals encourage people to use lean cuts of meat because most of the fat in animal products is unhealthful saturated fat, which can raise the risk of heart disease and cancer.
    Bethany Thayer, Detroit Free Press, 22 June 2024
Adjective
  • The specialty retailer’s chief financial officer, Robert Ball, said Abercrombie has seen about $5 million in adverse impact from tariffs during the second quarter, chiefly manifested in the cost of sales, and expects $90 million net impact from tariffs for the year.
    Kate Nishimura, Sourcing Journal, 4 Sep. 2025
  • This tool helps with reading, writing, summarizing, adverse-event profile reviews, label comparisons, clinical protocol assessments, and even generating database code.
    Sixteen Ramos, USA Today, 4 Sep. 2025

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Cite this Entry

“Noxious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/noxious. Accessed 6 Sep. 2025.

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