PERILOUS Synonyms: 66 Similar and Opposite Words

Q: How is the word 'perilous' distinct from other similar adjectives?

Some common synonyms of perilous are dangerous , hazardous , precarious , and risky . While all these words mean "bringing or involving the chance of loss or injury," perilous strongly implies the immediacy of danger. // perilous mountain roads

Q: When might 'dangerous' be a better fit than 'perilous'?

The words dangerous and perilous are synonyms, but do differ in nuance. Specifically, dangerous applies to something that may cause harm or loss unless dealt with carefully. // soldiers on a dangerous mission

Q: When is it sensible to use 'hazardous' instead of 'perilous'?

The synonyms hazardous and perilous are sometimes interchangeable, but hazardous implies great and continuous risk of harm or failure. // claims that smoking is hazardous to your health

Q: When can 'precarious' be used instead of 'perilous'?

While in some cases nearly identical to perilous , precarious suggests both insecurity and uncertainty. // earned a precarious living by gambling

Q: When would 'risky' be a good substitute for 'perilous'?

In some situations, the words risky and perilous are roughly equivalent. However, risky often applies to a known and accepted danger. // shied away from risky investments

perilous

adjective

ˈper-ə-ləs

Definition of perilous

as in dangerous

involving potential loss or injury a perilous journey through hostile territory

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How is the word perilous distinct from other similar adjectives?

Some common synonyms of perilous are dangerous, hazardous, precarious, and risky. While all these words mean "bringing or involving the chance of loss or injury," perilous strongly implies the immediacy of danger.

perilous mountain roads

When might dangerous be a better fit than perilous?

The words dangerous and perilous are synonyms, but do differ in nuance. Specifically, dangerous applies to something that may cause harm or loss unless dealt with carefully.

soldiers on a dangerous mission

When is it sensible to use hazardous instead of perilous?

The synonyms hazardous and perilous are sometimes interchangeable, but hazardous implies great and continuous risk of harm or failure.

claims that smoking is hazardous to your health

When can precarious be used instead of perilous?

While in some cases nearly identical to perilous, precarious suggests both insecurity and uncertainty.

earned a precarious living by gambling

When would risky be a good substitute for perilous?

In some situations, the words risky and perilous are roughly equivalent. However, 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 perilous But the advent of RSI might also be highly perilous for humanity, potentially marking the stage at which developers lose control of AI systems entirely. — Billy Perrigo, Time, 14 Oct. 2026 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 In these paint factories, young women performed the most perilous work, managing the production of pure white-lead that would later be combined with oils. — Wendy S. Walters, Architectural Digest, 12 Oct. 2026 These days, the college education that, in our time, cost about $20,000 for four years is under siege, regarded by some as a waste of time and money, by others as a perilous marination in dangerous ideas. — David Shribman, Christian Science Monitor, 10 Oct. 2026 See All Example Sentences for perilous

Recent Examples of Synonyms for perilous

Adjective

In November 2021, crew members took shelter inside their spacecraft after a Russian anti-satellite weapons test created a dangerous cloud of debris.

— Kurt Knutsson, FOXNews.com, 25 Oct. 2026
In 2015, Chicago’s public health department identified three cases of invasive meningococcal disease, a highly dangerous pathogen that can kill within hours.

— Julie Morita, Time, 25 Oct. 2026

Definition of dangerous

Adjective

If enough collisions occur, certain orbital regions could become extremely hazardous for future missions.

— Kurt Knutsson, FOXNews.com, 25 Oct. 2026
Today, the vast majority of this hazardous waste remains locked in temporary storage facilities across the globe.

— Mrigakshi Dixit, Interesting Engineering, 23 Oct. 2026

Definition of hazardous

Adjective

Revenue bonds are generally viewed as riskier than other types of government bonds, in part because they’re backed by the promise of revenue from a specific project — in this case, payment by individual borrowers.

— Audrey McGlinchy, Los Angeles Times, 24 Oct. 2026
The pain has been felt most acutely in the riskier credits with high-yield spreads rising about 70 basis points since late September.

— Justin Zacks, CNBC, 23 Oct. 2026

Definition of risky

Adjective

The Tallahassee Police Department said in a statement that 11 of the 12 were shot and that three victims had serious injuries, with one minor in serious condition.

— Samantha Cookinham, NBC news, 25 Oct. 2026
Bake this classic all the way through for a light and tender crumb, or cut the bake time short for serious gooey goodness in the center.

— Mary Shannon Wells, Southern Living, 25 Oct. 2026

Definition of serious

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“Perilous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/perilous. Accessed 28 Oct. 2026.

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