perilous

adjective

per·​il·​ous ˈper-ə-ləs 

ˈpe-rə-

: full of or involving peril

a perilous journey

perilously adverb

perilousness noun

Synonyms

• dangerous
• grave
• grievous
• hazardous
• jeopardizing
• menacing
• parlous
• risky
• serious
• threatening
• unhealthy
• unsafe
• venturesome

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

Nolan’s mythic action epic, shot with new Imax cameras, is based on the ancient Greek poem by Homer which follows Odysseus, King of Ithaca, and his perilous journey home after the Trojan War. —Rosy Cordero, Deadline, 10 Feb. 2025

Over the next three days, the serum changed hands multiple times, with teams of mushers and dogs navigating increasingly perilous conditions. —David Kindy, Smithsonian Magazine, 28 Jan. 2025

At such a potentially perilous moment, Mr. Ford said Canada was hobbled by lacking a strong bargaining position at the federal level, in part because Prime Minister Justin Trudeau has decided to step down and make way for a new party leader and prime minister. —Vjosa Isai, New York Times, 24 Jan. 2025

The fires will add a new dimension to the state’s already perilous insurance crisis. —Laura Paddison, CNN, 21 Jan. 2025

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

Kids Definition

perilous

adjective

per·​il·​ous ˈper-ə-ləs 

: full of or involving peril

perilously adverb

perilousness noun