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 next

as in dangerous

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

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

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 And with tight refurbishment and decommissioning timelines, along with fire safety and hazardous substance compliance risks, many organizations simply don’t have the time to experiment with circularity techniques and default to funneling recyclable textiles into waste management. —

Jennifer Bringle, Footwear News, 19 May 2026 Neem oil is hazardous for fish and aquatic invertebrates. —

Brandee Gruener, Southern Living, 19 May 2026 Examples include night-time inspection, repetitive handling, work in hazardous environments, and long periods of standing in service roles. —

John Koetsier, Forbes.com, 19 May 2026 Rough seas and hazardous underwater conditions repeatedly delayed search efforts as crews mapped and marked the cave entrance before pushing deeper inside. —

Stephen Sorace, FOXNews.com, 18 May 2026 See All Example Sentences for hazardous

Recent Examples of Synonyms for hazardous

Adjective

But pretty quickly, Wahl said that both the mother and police realized something more dangerous could be brewing.

— Amanda Lee Myers, USA Today, 19 May 2026
Sheets touched on the other key to his success — and any dangerous hitter’s success — in the above quote.

— Kevin Acee, San Diego Union-Tribune, 18 May 2026

Definition of dangerous

Browse Nearby Words

hazarding

hazardous

hazards

See all Nearby Words

Cite this Entry

Style

“Hazardous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hazardous. Accessed 22 May. 2026.

Copy Citation

Synonyms of hazardous

adjective

Synonym Chooser

Example Sentences

Browse Nearby Words

Cite this Entry

More from Merriam-Webster on hazardous

More from Merriam-Webster

Word of the Day

fraught

Popular in Grammar & Usage

5 Verbal Slip Ups and Language Mistakes

Regarding the Incorrect Use of 'Decimate'

Is it 'nerve-racking' or 'nerve-wracking'?

The Difference Between 'i.e.' and 'e.g.'

Democracy or Republic: What's the difference?

Popular in Wordplay

Strange Words for Body Functions

Where does 'curiosity killed the cat' come from?

What to Call the Inept, Incompetent, and Inferior

The Words of the Week - May 22

Insults and Compliments from Recent Slang

Popular

5 Verbal Slip Ups and Language Mistakes

Strange Words for Body Functions

Where does 'curiosity killed the cat' come from?

Games & Quizzes