ULTRAHAZARDOUS Synonyms: 66 Similar and Opposite Words

ultrahazardous

adjective

Definition of ultrahazardous

as in hazardous

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Example Sentences

Recent Examples of Synonyms for ultrahazardous

Adjective

These include dynamic proton radiography, materials science, neutron scattering, and nuclear physics, all operating at a facility authorized to use hazardous materials and handle classified data.

— Rupendra Brahambhatt, Interesting Engineering, 19 Sep. 2026
In regards to what is happening on the streets of NYC — Kaporos — thousands of young Cornish chickens are kept in the streets in crates, in hazardous and dangerous conditions.

— Voice of the People, New York Daily News, 19 Sep. 2026

Definition of hazardous

Adjective

Harry is known for speaking out in high-profile campaigns about the harmful impact of technology on young people.

— Sophie Tanno, CNN Money, 23 Sep. 2026
Too often, environmental advocates insist on the elimination of poaching, logging, and other harmful activities while remaining wholly unfamiliar with the factors at play that lead to predation, neglect, and abuse of nature.

— Juliet Kinsman, Condé Nast Traveler, 22 Sep. 2026

Definition of harmful

Adjective

Republicans are starting to realize that many of their president’s actions are detrimental to their extended political livelihoods.

— Laura Washington, Chicago Tribune, 23 Sep. 2026
Garofalo and Cosco were among a scant few women who have chosen – or been able – to escape their crime families, albeit with inarguably detrimental results.

— Barbie Latza Nadeau, CNN Money, 21 Sep. 2026

Definition of detrimental

Adjective

Never mix vinegar with bleach, as the combination can create dangerous chlorine gas.

— The Spruce, The Spruce, 20 Sep. 2026
As the news of the helicopter crash spread, media crews from the bus accident scene began rushing to the helicopter site and were told by law enforcement to evacuate because the situation was too dangerous, NBC4 footage showed.

— Dalia Faheid, CNN Money, 20 Sep. 2026

Definition of dangerous

Adjective

But the specific way markets are taking root—with much of the population too poor to participate meaningfully, with no rule of law, and with the gap between winners and losers steadily widening—is pernicious for the country’s future.

— Will Freeman, Foreign Affairs, 17 Sep. 2026
Most sinister of all, the documentary suggests Musk’s real goal in getting into the White House was to access data on all Americans, once again to feed his pernicious AI dreams.

— Matthew Carey, Deadline, 8 Sep. 2026

Definition of pernicious

Adjective

The ultimate distinction, Raji said, is whether an adverse finding produces consequences.

— Barbara Booth, CNBC, 16 Sep. 2026
Rather than fight an injunction motion — and potentially be forced to appeal an adverse ruling — Paramount chose instead to concede the issue and concentrate its trial defense.

— Gene Maddaus, Variety, 15 Sep. 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

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ultrafine

ultrahazardous

ultraheavy

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“Ultrahazardous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/ultrahazardous. Accessed 28 Sep. 2026.

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Synonyms of ultrahazardous

adjective

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