ultrahazardous

adjective

Definition of ultrahazardousnext
as in hazardous

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Example Sentences

Recent Examples of Synonyms for ultrahazardous
  1. hazardous
  2. harmful
  3. detrimental
  4. dangerous
  5. pernicious
  6. injurious
  7. adverse
  8. deleterious
Adjective
  • Forecasters said flash flood potential and hazardous coastal conditions across east Central Florida are the main concerns heading into the week.
    — Felix Rodriguez, The Orlando Sentinel, 1 Nov. 2026
  • Oil, gas and chemical plants are among the most hazardous and most costly places to operate.
    — Prabhat Ranjan Mishra, Interesting Engineering, 30 Oct. 2026
Definition of hazardous
Adjective
  • If our minds are constantly running at full throttle, potentially harmful molecules might keep piling up faster than the brain can dispose of them.
    — Cody Cottier, Scientific American, 4 Nov. 2026
  • Earth's ozone layer acts as a planetary sunscreen, shielding humans, animals, and plants from harmful ultraviolet (UV) radiation.
    — Dan Peck, ABC News, 4 Nov. 2026
Definition of harmful
Adjective
  • The company still faces numerous personal injury claims and a separate federal case involving a group of nationwide school districts that also focus on allegations that apps like Instagram have had detrimental effects on the well being of children.
    — Jonathan Vanian, CNBC, 21 Oct. 2026
  • Often, those firms’ IT heads think those changes are detrimental.
    — Scharon Harding, ArsTechnica, 21 Oct. 2026
Definition of detrimental
Adjective
  • People talking to an AI in an abusive and cruel way are more likely to be associated with trying to get the AI model to engage in dangerous requests, like trying to get around an AI’s safety guardrails, Campbell added.
    — Hadas Gold, CNN Money, 1 Nov. 2026
  • Hazing involves requiring new or potential recruits to the military or college fraternities to perform strenuous, humiliating or dangerous tasks.
    — Natasha Holt, FOXNews.com, 1 Nov. 2026
Definition of dangerous
Adjective
  • Courtesy of WorldSkills Is one of the world’s most pernicious social stigmas finally lifting?
    — the Monitor's Editorial Board, Christian Science Monitor, 8 Oct. 2026
  • Obscured Releasing has acquired North American distribution rights to The Drug in Our Pocket, a documentary by Anne Sundberg about the pernicious effects on young people of constant smartphone use.
    — Matthew Carey, Deadline, 2 Oct. 2026
Definition of pernicious
Adjective
  • Oliva was being held on an additional bond of $3,650 on charges of possession of a firearm while having a domestic violence injunction, willful disregard of environmental regulations and nuisances injurious to health.
    — David Goodhue, Miami Herald, 21 Oct. 2026
  • White House advisers have argued that his vision would be politically injurious ahead of the midterms.
    — Dhruv Khullar, New Yorker, 25 Aug. 2026
Definition of injurious
Adjective
  • Floodplain alterations cannot have adverse upstream or downstream effects, and earthen flood barriers, or any other interruption to the natural flow of flood water, is prohibited.
    — Matthew Adams, Fort Worth Star-Telegram, 30 Oct. 2026
  • Studies have found oil wells can emit carcinogens and are linked to adverse health effects including respiratory issues, headaches, throat irritation and other problems.
    — Los Angeles Times, Los Angeles Times, 28 Oct. 2026
Definition of adverse
Adjective
  • Since wood smoke didn’t cause these deleterious effects, the researchers believe that metals may be involved in the most damaging forms of pollution to the brain.
    — Frank Landymore, Futurism, 28 Oct. 2026
  • The backlash against this perfectly reasonable post demonstrates the deleterious effect of mass immigration on our democratic system.
    — Matthew Ablon, CBS News, 14 Sep. 2026
Definition of deleterious
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.

Browse Nearby Words

ultrafine
ultrahazardous
ultraheavy
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Cite this Entry

“Ultrahazardous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/ultrahazardous. Accessed 7 Nov. 2026.

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