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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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 Residents have been complaining loudly about impacts from the fire, most notably citing issues such as noxious odors, vermin, flies and rodents. Tom Bray, Daily News, 14 July 2026 Lineage hired contractors who are measuring this noxious gas and other pollution. Tony Briscoe, Los Angeles Times, 2 July 2026 But the real pleasure is the 303 basslines that squirm in between the drums, coating the soundscapes of the tracks in grime and noxious soot. Andrew Ryce, Pitchfork, 1 July 2026 In other words, France isn’t exactly off the hook for its own noxious pollution. Joe Wilkins, Futurism, 1 July 2026 See All Example Sentences for noxious
Recent Examples of Synonyms for noxious
Adjective
  • Wildfire smoke contains noxious or poisonous gases and particulate matter, tiny particles that can be inhaled deep into the lungs, affecting people with respiratory problems, says the Environmental Protection Agency.
    Janet Loehrke, USA Today, 16 July 2026
  • How plants poisonous to dogs cause harm Not all toxic plants affect dogs the same way, but many share similar chemicals that attack the digestive system.
    Ryan Brennan, Fort Worth Star-Telegram, 15 July 2026
Adjective
  • Your liver is responsible for breaking down toxins and filtering them out of the body, essentially detoxifying you from harmful substances and chemicals.
    Angelica Bottaro, Verywell Health, 22 July 2026
  • At our previous Yale CEO Caucus, over two-thirds of CEOs surveyed told us that Trump’s tariffs had been harmful to their own businesses, and 80% said that tariff costs had been passed on in part to consumers.
    Jeffrey Sonnenfeld, Fortune, 22 July 2026
Adjective
  • This is beyond disgusting, photos like this should be private.
    StyleCaster Editors, StyleCaster, 24 July 2026
  • His shirt was soaked down below his collarbones, clingy and disgusting.
    Literary Hub, Literary Hub, 22 July 2026
Adjective
  • As toxic levels of gas have been detected, teams wearing oxygen gear raced to find survivors on Tuesday, the outlet reported.
    Gina Kalsi, PEOPLE, 22 July 2026
  • Research shows toxic culture is the leading cause of attrition, far surpassing compensation.
    Nell Derick Debevoise Dewey, Forbes.com, 21 July 2026
Adjective
  • Experts agree that allowing external services to access Apple’s and Google’s operating systems could be dangerous for security and user privacy.
    Lisa Eadicicco, CNN Money, 19 July 2026
  • Sources additionally say that officers have burnt out while working overtime month after month — all on top of functioning in an already tense and dangerous environment, likening the situation to a powder keg ready to blow.
    Anna Giaritelli, The Washington Examiner, 19 July 2026
Adjective
  • The deals defined one of the ugliest chapters of Russia’s transition to capitalism in the 1990s.
    Simon Shuster, The Atlantic, 17 July 2026
  • Leaders must be grounded in self-awareness and their influence, leaning into emotional intelligence and humility; recognizing that different styles shape how people show up amid many influences, good, bad and ugly.
    Expert Panel®, Forbes.com, 17 July 2026
Adjective
  • From downtown Los Angeles to the San Gabriel Valley, tens of thousands were enveloped in unhealthful levels of smoke, even as some local officials told residents that the air posed no danger.
    Tony Briscoe, Los Angeles Times, 2 July 2026
  • The soil may contain pathogens, pesticides and other unhealthful things.
    Joan Morris, Mercury News, 9 Feb. 2026
Adjective
  • But this isn’t because of potential health risks or adverse effects in-flight—cabin crew simply dislike pouring it because of its excessive fizziness.
    Stacey Leasca, Travel + Leisure, 17 July 2026
  • The scientific debate Scientists do not always agree on what counts as an adverse effect of mindfulness.
    Ronald S. Green, The Conversation, 16 July 2026

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Cite this Entry

“Noxious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/noxious. Accessed 26 Jul. 2026.

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