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 Helpful sources at your university agricultural extension program can usually confirm the identity of noxious weeds like giant hogweed and poison hemlock. Natalie Krebs, Outdoor Life, 26 Mar. 2026 Orson Scott Card wrote a whole series preoccupied with the devastating results of interspecies misunderstanding and intolerance, then followed it up with various noxious statements cementing his homophobia. Sara Holdren, Vulture, 24 Mar. 2026 Theroux attempts to speak with women connected to his noxious subjects, but his efforts are largely thwarted. Alison Foreman, IndieWire, 19 Mar. 2026 Idaho’s pest management programs traditionally deal with agrarian problems, like noxious weeds, or agricultural raiders like pocket gophers, marmots or voracious insects. Mark Dee march 17, Idaho Statesman, 17 Mar. 2026 See All Example Sentences for noxious
Recent Examples of Synonyms for noxious
Adjective
  • Both fruit and tuber are poisonous.
    Joshua Siskin, Oc Register, 16 Apr. 2026
  • When Floyd is found dead at a community pool surrounded by a poisonous cocktail and a vintage Playgirl magazine, two detectives (Richard Jenkins and Joy Sunday) begin unraveling the bizarre chain of events that led to his death.
    Clayton Davis, Variety, 15 Apr. 2026
Adjective
  • The new safety measures come after a barrage of lawsuits from families alleging the platform doesn't do enough to shield children from harmful content and communication with older users.
    Mary Cunningham, CBS News, 13 Apr. 2026
  • Vaccines can train your immune system to recognize and fight harmful germs.
    Sukhman Rekhi, Verywell Health, 13 Apr. 2026
Adjective
  • This was in itself disgusting but also came to represent the city’s problems.
    Rachel Sugar, Curbed, 8 Apr. 2026
  • Living under an openly misogynistic president may have felt freakish in 2017, but by his second term, bigotry became yet another disgusting norm.
    Ben Travers, IndieWire, 2 Apr. 2026
Adjective
  • The former Exide Technologies plant in Vernon melted down pallets of lead-acid car batteries in blast furnaces for nearly a century, blanketing up to 10,000 nearby properties with toxic dust, according to state officials.
    Tony Briscoe, Los Angeles Times, 11 Apr. 2026
  • Oil prices are once again surging in the wake of war in the Middle East, driving up the cost of gasoline, diesel and jet fuel and threatening a return to stagflation – the toxic mix of higher prices and slower growth that made economic life so miserable a half century ago.
    ABC News, ABC News, 11 Apr. 2026
Adjective
  • The agency also rescinded the legal and scientific basis that had long established greenhouse gases as dangerous to public health.
    Stephanie Armour, CBS News, 13 Apr. 2026
  • From a darkly comic road rage incident to something more ambiguous, and potentially more dangerous; from the open roads of Southern California to an exclusive country club in Montecito; and from a couple of strangers in conflict to two actual couples in conflict with each other — and themselves.
    Ryan Coleman, Entertainment Weekly, 13 Apr. 2026
Adjective
  • While not the pastor of the United States, Trump surely represents the face of the United States on a daily basis, and that face is an ugly one.
    Chicago Tribune, Chicago Tribune, 9 Apr. 2026
  • Featuring the good, the bad and the ugly, ‘Look of the Week’ is a regular series dedicated to unpacking the most talked about outfit of the last seven days.
    Leah Dolan, CNN Money, 9 Apr. 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
  • The charity seeks the court’s intervention, protection, and restitution following a coordinated adverse media campaign conducted since 25 March 2025 that has caused operational disruption and reputational harm to the charity, its leadership, and its strategic partners.
    Dominic Patten, Deadline, 10 Apr. 2026
  • Extend it to four seconds to ensure safe spacing in adverse conditions.
    Bay Area Weather Report, Mercury News, 10 Apr. 2026

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Cite this Entry

“Noxious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/noxious. Accessed 17 Apr. 2026.

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