ULTRAHAZARDOUS Synonyms: 66 Similar and Opposite Words

ultrahazardous

adjective

Definition of ultrahazardous

as in hazardous

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Recent Examples of Synonyms for ultrahazardous

Adjective

Ensure heat is working so tenants don’t need space heaters, which can be particularly hazardous in buildings with older electrical systems.

— Lillian Bonsignore, New York Daily News, 4 Oct. 2026
The action comes as Livingston locals raised concerns about the film’s impact on local business — and notably the city’s sole food bank — as well as improper notification about hazardous stunts.

— Payton Turkeltaub, Variety, 4 Oct. 2026

Definition of hazardous

Adjective

While the baits are not harmful to pets, eating several may cause mild stomach upset.

— Dan Raby, CBS News, 7 Oct. 2026
The film primarily follows Frances Haugen (Mikey Madison), a Facebook employee in the company’s civic integrity team, the group tasked with making sure Facebook acts responsibly and avoids the harmful impacts of its product.

— Bilge Ebiri, Vulture, 7 Oct. 2026

Definition of harmful

Adjective

That's on the heels of a 41-7 blowout at Northwestern that was ugly enough for Deion Sanders to dismiss a handful of players for conduct detrimental to the team days later.

— Amber Harding OutKick, FOXNews.com, 30 Sep. 2026
To that point, Carter wrote that if the NFL’s relationship with Fanatics were detrimental to the marketplace, there would be higher prices for consumers.

— Michael McCann, Sportico.com, 30 Sep. 2026

Definition of detrimental

Adjective

Meanwhile, the financial clout of the industry has grown considerably, resulting in a new, more dangerous problem.

— Kent Sepkowitz, STAT, 5 Oct. 2026
Attempting to de-escalate the scare, Rospotrebnadzor declared the regional sanitary situation stable after secondary testing showed no traces of dangerous pathogens linked to Shipilova’s research.

— Mrigakshi Dixit, Interesting Engineering, 5 Oct. 2026

Definition of dangerous

Adjective

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
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

Definition of pernicious

Adjective

Retaliation is described as an adverse employment action connected to an activity protected by a law under its jurisdiction.

— William Jones, Sacbee.com, 2 Oct. 2026
Eating Sweetened Foods With Protein Eating protein alongside sugary snacks can help stabilize your blood sugar and minimize the spikes that lead to a host of adverse health effects.

— Kelly Burch, Verywell Health, 2 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

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Browse Nearby Words

ultrafine

ultrahazardous

ultraheavy

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“Ultrahazardous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/ultrahazardous. Accessed 10 Oct. 2026.

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Synonyms of ultrahazardous

adjective

Example Sentences

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