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 Following the quake, a tsunami advisory was issued, with the potential for hazardous tsunami waves possible for coasts within 300 kilometers of the earthquake epicenter. Abc News, ABC News, 24 June 2026 At the scene, CMPD brought in three armored vehicles and a mobile tactical shield designed to transport officers into potentially hazardous situations. Zaire Breedlove, Charlotte Observer, 24 June 2026 High-voltage lithium-ion battery systems that power electric vehicles are especially prone to thermal runaway if damaged, which can produce intense heat, toxic gases and prolonged fire conditions requiring specialized firefighting and hazardous materials personnel to control the incident. Reeti Malhotra, Sacbee.com, 24 June 2026 Sports Minister Marie Barsacq urged caution, warning against swimming in unauthorized or hazardous areas despite the temptation to cool off. Rena Rowe, The Washington Examiner, 23 June 2026 See All Example Sentences for hazardous
Recent Examples of Synonyms for hazardous
Adjective
  • Others develop dangerous fluctuations in blood pressure and abnormal heart rhythms because the autonomic nervous system becomes affected.
    Faye Chiu, CNN Money, 23 June 2026
  • Sometimes, the streets appear glittering; other times, seedy and dangerous.
    Los Angeles Times, Los Angeles Times, 22 June 2026
Adjective
  • Understanding the gravity of a red flag warning and adhering to these precautions is paramount in averting wildfires during these perilous conditions.
    CA Weather Bot, Sacbee.com, 19 June 2026
  • They are packed by smugglers into small and unsafe boats, with thousands dying during the perilous sea journey.
    ABC News, ABC News, 19 June 2026
Adjective
  • It is meant to make a major war, especially a nuclear war, too risky for the enemy to start.
    Atharva Gosavi, Interesting Engineering, 23 June 2026
  • Wall Street amplified the problem by bundling risky mortgages into securities that spread losses throughout the financial system.
    Greg Rosalsky, NPR, 23 June 2026
Adjective
  • What Research Shows About Cancer in Dogs While there is no evidence that turkey tail shrinks tumors, the mushroom has drawn real scientific interest as a complementary therapy for serious illness.
    Samantha Agate, Kansas City Star, 26 June 2026
  • The new guidance was heavily criticized by health groups, which argued the decision could sow confusion and leave children vulnerable to serious disease.
    Joe Walsh, CBS News, 26 June 2026
Adjective
  • They are packed by smugglers into small and unsafe boats, with thousands dying during the perilous sea journey.
    ABC News, ABC News, 19 June 2026
  • Remaining inside a vehicle during a tornado is unsafe.
    STAR-TELEGRAM WEATHER BOT, Fort Worth Star-Telegram, 19 June 2026

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Cite this Entry

“Hazardous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hazardous. Accessed 26 Jun. 2026.

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