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

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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 policy does say the tactic should not be used on trucks carrying hazardous materials, pickup trucks with passengers in the bed of the truck, vans or buses occupied with passengers who appear to be victims or motorcycles. — Arkansas Online, 14 Aug. 2026 According to Deep Robotics, DR02 is designed for industrial, hazardous, and outdoor applications, including factory operations, equipment inspection, emergency response, infrastructure maintenance, and work around high-voltage electrical systems. — Jijo Malayil, Interesting Engineering, 14 Aug. 2026 Aftershocks have added another danger to an already hazardous operation. — Antonio María Delgado, Miami Herald, 14 Aug. 2026 The home was ventilated and checked for any hazardous air conditions, according to Garrahy. — Justin Muszynski, Hartford Courant, 13 Aug. 2026 See All Example Sentences for hazardous

Recent Examples of Synonyms for hazardous

Adjective

On Sunday, storms brought dangerous flash flooding to the area around the Aspen Acres burn scar.

— Christa Swanson, CBS News, 17 Aug. 2026
That makes the world a more dangerous place, where a mistake by just one actor could ignite a regional firestorm, with a US military weakened by Iran unable to ensure American security.

— Brad Lendon, CNN Money, 17 Aug. 2026

Definition of dangerous

Adjective

Severe weather cut power to nearly 1 million customers in the Midwest as perilous thunderstorms and extreme wind gusts pummeled the region Tuesday.

— CBS News, CBS News, 11 Aug. 2026
Severe weather cut power Tuesday in the Chicago area and northwestern Indiana as perilous storms pummeled the region, darkening the sky and carrying extreme wind gusts across state lines.

— ABC News, ABC News, 11 Aug. 2026

Definition of perilous

Adjective

The work is risky because miners typically do not have enough protection and the accidents are often deadly.

— ABC News, ABC News, 18 Aug. 2026
Today most developments focus on robotic interventions that avoid the expensive and risky prospect of lofting repair worker astronauts into orbit.

— Tom Metcalfe, Scientific American, 18 Aug. 2026

Definition of risky

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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 Aug. 2026.

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Synonyms of hazardous

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