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 work included thinning trees, removing hazardous fuels and restoring forest health. — Karen Morfitt, CBS News, 26 Aug. 2026 Robots had 30 minutes to identify hazardous substances, locate and shut off three open valves of different types, spot a fire, and then find a fire extinguisher to put it out. — Jeremy Hsu, ArsTechnica, 25 Aug. 2026 Quick reductions in visibility could result in hazardous driving conditions during this mornings rush hour. — Nc Weather Bot, Charlotte Observer, 25 Aug. 2026 Operating below this 300-million-barrel threshold pushes the aging infrastructure into uncharted and hazardous territory. — Siddharth Misra, Fortune, 25 Aug. 2026 See All Example Sentences for hazardous

Recent Examples of Synonyms for hazardous

Adjective

Heaping credit onto Espada is dangerous, but so is blaming him for every game that goes awry.

— Chandler Rome, New York Times, 31 Aug. 2026
That’s a dangerous prospect for any country, but especially for Singapore, crammed into a space smaller than New York City.

— Angelica Ang, Fortune, 30 Aug. 2026

Definition of dangerous

Adjective

Scientists previously created tiny diving suits for Madagascar hissing cockroaches that could be used in perilous search operations, according to a study published in the journal Nature Communications.

— Devika Rao, TheWeek, 3 Sep. 2026
Congress has eliminated the threat of a politically perilous government shutdown this fall.

— Sam Gringlas, NPR, 1 Sep. 2026

Definition of perilous

Adjective

At the same time — despite Tuesday’s move — investor appetite for riskier assets like stocks continues to climb.

— Rob Wile, NBC news, 1 Sep. 2026
Knowing a bailout is coming, however, may inadvertently encourage farmers to sustain their dependence on the risky Chinese export market.

— Chad P. Bown, Foreign Affairs, 1 Sep. 2026

Definition of risky

Adjective

The North Lawn tenants had been involved in a yearslong dispute with multiple landlords over unsafe living conditions.

— Dylan Lysen, Kansas City Star, 30 Aug. 2026
Well-loved and used items that are broken, damaged beyond repair, unsafe, or heavily stained or soiled should be thrown out.

— Karen Brewer Grossman, Southern Living, 29 Aug. 2026

Definition of unsafe

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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 5 Sep. 2026.

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Synonyms of hazardous

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