Definition of hazardousnext

Synonym Chooser

How is the word hazardous distinct from other similar adjectives?

Some common synonyms of hazardous are dangerous, perilous, precarious, and risky. While all these words mean "bringing or involving the chance of loss or injury," hazardous implies great and continuous risk of harm or failure.

claims that smoking is hazardous to your health

When is dangerous a more appropriate choice than hazardous?

In some situations, the words dangerous and hazardous are roughly equivalent. However, dangerous applies to something that may cause harm or loss unless dealt with carefully.

soldiers on a dangerous mission

When could perilous be used to replace hazardous?

Although the words perilous and hazardous have much in common, perilous strongly implies the immediacy of danger.

perilous mountain roads

In what contexts can precarious take the place of hazardous?

While the synonyms precarious and hazardous are close in meaning, precarious suggests both insecurity and uncertainty.

earned a precarious living by gambling

Where would risky be a reasonable alternative to hazardous?

While in some cases nearly identical to hazardous, risky often applies to a known and accepted danger.

shied away from risky investments

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 hazardous Drivers will discover that the design causes unavoidable backups in both directions on Broward Boulevard, plus confusing and hazardous lane changes to avoid traffic flowing from the opposite direction. Sun Sentinel Editorial Board, Sun Sentinel, 28 Apr. 2026 Officials from the Maryland Department of the Environment are also investigating the scene to determine whether hazardous materials in the roofing company’s building may have contributed to any additional damage. Lily Carey, Baltimore Sun, 28 Apr. 2026 As part of their investigations, the Army Corps of Engineers gathers soil samples and checks for hazardous materials. Taylor O'Connor, Kansas City Star, 27 Apr. 2026 From there, things were less hazardous. Bill Plunkett, Oc Register, 26 Apr. 2026 See All Example Sentences for hazardous
Recent Examples of Synonyms for hazardous
Adjective
  • Gabriel Basso stars as Sutherland, a formerly low-level FBI agent who has taken on increasingly dangerous assignments as part of a counterintelligence group within the bureau called Night Action.
    Rick Porter, HollywoodReporter, 4 May 2026
  • Bessent has compared the Fed's growing balance sheet to a dangerous lab experiment.
    Steve Liesman,Matt Peterson, CNBC, 4 May 2026
Adjective
  • Far from benign, some experts say the videos can skew how people view and even interact with wildlife — potentially leading to perilous encounters.
    Lila Seidman, Los Angeles Times, 2 May 2026
  • It's become a more perilous occupation to be President of the United States, or a congressional leader, or to be a state legislator in Minnesota, or to be the spouse of a former House speaker.
    Dana Taylor, USA Today, 28 Apr. 2026
Adjective
  • His incredulity about their increasingly risky adventures—this is the one that involves a Pontiac Fiero in outer space—becomes one of the film’s running gags.
    Hua Hsu, New Yorker, 29 Apr. 2026
  • Pakistan has become one of the most consequential players in the Iran war, taking on a risky mediation role that draws on its ties with Tehran while keeping its financial lifeline with the Gulf intact.
    Mohammed Sergie, semafor.com, 28 Apr. 2026
Adjective
  • Half a century later, the nation’s environmental problems are a lot less visible, but not, for that reason, any less serious.
    Elizabeth Kolbert, New Yorker, 30 Apr. 2026
  • Even in healthy children, measles can cause serious illness and death.
    Thao Nguyen, USA Today, 30 Apr. 2026
Adjective
  • The upshot is not only that Jewish Britons feel unsafe.
    Alexander Smith, NBC news, 1 May 2026
  • His parents’ dysfunctional relationships made for an unsafe environment at home, so the decision was made to send him to the Caribbean nation to stay with relatives.
    Carlos Aguilar, Los Angeles Times, 30 Apr. 2026

Browse Nearby Words

Cite this Entry

“Hazardous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hazardous. Accessed 7 May. 2026.

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