perilous

adjective

per·​il·​ous ˈper-ə-ləs 

ˈpe-rə-

: full of or involving peril

a perilous journey

perilously adverb

perilousness noun

Synonyms of perilous

• dangerous
• hazardous
• risky
• serious

Choose the Right Synonym for perilous

dangerous, hazardous, precarious, perilous, risky mean bringing or involving the chance of loss or injury.

dangerous applies to something that may cause harm or loss unless dealt with carefully.

soldiers on a dangerous mission

hazardous implies great and continuous risk of harm or failure.

claims that smoking is hazardous to your health

precarious suggests both insecurity and uncertainty.

earned a precarious living by gambling

perilous strongly implies the immediacy of danger.

perilous mountain roads

risky often applies to a known and accepted danger.

shied away from risky investments

Examples of perilous in a Sentence

a perilous journey across the mountains

a perilous journey through hostile territory

Recent Examples on the Web

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

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

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 Persian Gulf nations. — Jamey Keaten, Los Angeles Times, 11 Oct. 2026

Word History

Etymology

Middle English perilous, perelous, borrowed from Anglo-French perilleus, perillous, going back to Latin perīculōsus, from perīculum "test, risk, peril entry 1" + -ōsus -ous

First Known Use

14th century, in the meaning defined above

Rhymes for perilous

• carolus
• garrulous
• querulous
• puberulous

Kids Definition

perilous

adjective

per·​il·​ous ˈper-ə-ləs 

: full of or involving peril

perilously adverb

perilousness noun