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 Director Allen paces the reveals and developments – whether noxious or as sweet as the first blush of love in little Zonia and neighbor boy Reuben (Jackson Edward Davis at the review performance) – with an artful sense of the narrative’s timings and rhythms. Greg Evans, Deadline, 25 Apr. 2026 The practice has had horrible consequences for the Black, working class neighborhood where the turbines are located, whose residents are stuck breathing xAI’s noxious exhaust. Joe Wilkins, Futurism, 16 Apr. 2026 Dry fields are also vulnerable to noxious weeds like leafy spurge and toadflax, which are toxic to cattle and unpalatable to native ungulates like deer and pronghorn antelope. Krista Kafer, Denver Post, 7 Apr. 2026 Bully feels custom-designed to please the diehards exhausted by his noxious antics. Kieran Press-Reynolds, Pitchfork, 1 Apr. 2026 See All Example Sentences for noxious
Recent Examples of Synonyms for noxious
Adjective
  • Health officials urged anybody who may have eaten a poisonous mushroom to seek medical care immediately and contact the California Poison Control Hotline.
    Gabrielle Rockson, PEOPLE, 13 May 2026
  • Anyone who may have eaten a poisonous mushroom should seek medical care immediately and contact the California Poison Control Hotline at 800-222-1222.
    Tim Fang, CBS News, 13 May 2026
Adjective
  • Prosecutors maintain the search was legal because it was conducted in conjunction with an arrest and officers were following Altoona police protocols that require them to check for dangerous items that could be harmful to them or the public.
    Michael R. Sisak, Los Angeles Times, 18 May 2026
  • Santos is charged with distributing food with a harmful substance, according to court records obtained by the Telegram & Gazette, part of the USA TODAY Network.
    Drew Pittock, USA Today, 18 May 2026
Adjective
  • How on Earth could this Wild team, after dominating the first period and taking a 3-0 lead with a chance to keep its season alive and force a Game 6, collapse in such an absolutely disgusting fashion?
    Michael Russo, New York Times, 14 May 2026
  • Just days ago, the CDC announced that over 100 passengers and more than a dozen crew members on a different ship, the Caribbean Princess, have been infected by norovirus—a less fatal but more disgusting illness.
    Hillary Busis, Vanity Fair, 11 May 2026
Adjective
  • Could the chicken from which the thigh and breast meat came, have consumed, weeks earlier, a toxic amount of psychedelics?
    Weike Wang, New Yorker, 17 May 2026
  • Most illnesses are linked to amatoxin-containing mushrooms, including death caps (Amanita phalloides) and western destroying angels (Amanita ocreata), both highly toxic species that can closely resemble edible mushrooms.
    Anthony Thompson, USA Today, 16 May 2026
Adjective
  • But pretty quickly, Wahl said that both the mother and police realized something more dangerous could be brewing.
    Amanda Lee Myers, USA Today, 19 May 2026
  • Sheets touched on the other key to his success — and any dangerous hitter’s success — in the above quote.
    Kevin Acee, San Diego Union-Tribune, 18 May 2026
Adjective
  • Last year, the two teams met in London in an ugly 13-11 Denver win.
    Antwan Staley, New York Daily News, 15 May 2026
  • With respect to humor’s inherent subjectivity, the appallingly ugly aesthetics of the AI overwhelm any possible comedic sensibility on display.
    Vikram Murthi, IndieWire, 15 May 2026
Adjective
  • The soil may contain pathogens, pesticides and other unhealthful things.
    Joan Morris, Mercury News, 9 Feb. 2026
  • The change comes amid concerns about fireworks causing unhealthful air.
    Rong-Gong Lin II, Los Angeles Times, 19 June 2025
Adjective
  • Post-Adverse Outcome Disclosure Obligations The replacement bill also creates disclosure obligations after an adverse outcome.
    Alonzo Martinez, Forbes.com, 15 May 2026
  • Prolonged stress can have adverse consequences, especially for pregnant mothers, children and critically ill patients.
    Adam Harrington, CBS News, 14 May 2026

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Cite this Entry

“Noxious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/noxious. Accessed 19 May. 2026.

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