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
  • If enough collisions occur, certain orbital regions could become extremely hazardous for future missions.
    — Kurt Knutsson, FOXNews.com, 25 Oct. 2026
  • Today, the vast majority of this hazardous waste remains locked in temporary storage facilities across the globe.
    — Mrigakshi Dixit, Interesting Engineering, 23 Oct. 2026
Definition of hazardous
Adjective
  • Social media giant Meta was hit with a class action lawsuit in Australia on behalf of children and teenagers who allegedly suffered harm over the addictive design features and exposure to harmful content on its platforms Facebook and Instagram.
    — Chad de Guzman, Time, 22 Oct. 2026
  • Their contracts can run hundreds of pages, making harmful terms easy to bury.
    — Emma Witman, Fortune, 21 Oct. 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
  • In November 2021, crew members took shelter inside their spacecraft after a Russian anti-satellite weapons test created a dangerous cloud of debris.
    — Kurt Knutsson, FOXNews.com, 25 Oct. 2026
  • In 2015, Chicago’s public health department identified three cases of invasive meningococcal disease, a highly dangerous pathogen that can kill within hours.
    — Julie Morita, Time, 25 Oct. 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
  • In recent years, cocoa prices have surged due to adverse weather across key West African producing regions.
    — , CNBC, 23 Oct. 2026
  • Batie-Smoose seeks reinstatement or a comparable job, compensation and correction of adverse personnel records.
    — Jackson Thompson OutKick, FOXNews.com, 22 Oct. 2026
Definition of adverse
Adjective
  • 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
  • During this time, bogs, marshes, and other wetlands, historically seen as disease-ridden and deleterious to human health, were reevaluated by scientists and conservationists as valuable wildlife habitats.
    — Encyclopedia Britannica, Encyclopedia Britannica, 24 July 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 29 Oct. 2026.

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