HAZARDOUS Synonyms: 66 Similar and Opposite Words

Q: 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

Q: 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

Q: 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

Q: 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

Q: 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

hazardous

adjective

ˈha-zər-dəs

Definition of hazardous

as in dangerous

involving potential loss or injury a hazardous journey across the arctic ice

Synonyms & Similar Words

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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 The robotic system removed the need for manual work in hazardous areas. — Aman Tripathi, Interesting Engineering, 16 Oct. 2026 At the Shore, conditions will become especially rough Friday night into Saturday, with strong winds and hazardous boating conditions. — Bill Kelly, CBS News, 15 Oct. 2026 The facility has sign for consumer advisory for undercooked food, and the potentially hazardous items are marked, but the sign is lacking asterisks. — Arkansas Online, 12 Oct. 2026 The production was shut down in Livingston, Montana last Saturday when locals complained about the production’s impact on the Livingston food bank and improper warnings about hazardous stunts. — Pat Saperstein, Variety, 10 Oct. 2026 See All Example Sentences for hazardous

Recent Examples of Synonyms for hazardous

Adjective

Swimmers should remain out of the water due to dangerous surf conditions.

— NC Weather Bot, Charlotte Observer, 18 Oct. 2026
Fresh to strong winds will produce dangerous boating conditions, high surf, life-threatening rip currents, and moderate beach erosion through at least the first half of the coming week, forecasters said.

— Felix Rodriguez, The Orlando Sentinel, 18 Oct. 2026

Definition of dangerous

Adjective

At least 84 people remained missing in one of the deadliest shipwrecks yet on the popular but perilous crossing from the Horn of Africa to the Arabian Peninsula, where many migrants seek work in rich Gulf nations.

— JAMEY KEATEN, Arkansas Online, 12 Oct. 2026
But the pincer movement—the armed invasion from the East, and tariffs from the West—is leaving steelmaking in Ukraine in a perilous position.

— Kamal Ahmed, Fortune, 12 Oct. 2026

Definition of perilous

Adjective

The fact fraternity alumni donate more makes getting rid of fraternities financially risky for schools.

— Jens Ludwig, Chicago Tribune, 18 Oct. 2026
Representatives Lori Trahan and Jay Obernolte have advanced the FRONTIER Act, which would authorize government intervention against risky models and override some state laws.

— Aamir Khollam, Interesting Engineering, 17 Oct. 2026

Definition of risky

Adjective

The subject is of particular interest at CBS News, where Editor-in-Chief Bari Weiss has repeatedly encouraged the network’s journalists to dedicate serious resources to finding a potential link.

— semafor.com, semafor.com, 19 Oct. 2026
Illinois Republicans are angry that the congressional map is deliberately drawn to their serious disadvantage, with some districts almost comically gerrymandered.

— John T. Shaw, Chicago Tribune, 18 Oct. 2026

Definition of serious

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hazarding

hazardous

hazards

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“Hazardous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hazardous. Accessed 21 Oct. 2026.

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Synonyms of hazardous

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