perilous

adjective

per·​il·​ous ˈper-ə-ləs How to pronounce perilous (audio)
ˈpe-rə-
Synonyms of perilousnext
: full of or involving peril
a perilous journey
perilously adverb
perilousness noun
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
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.
Understanding the gravity of a red flag warning and adhering to these precautions is paramount in averting wildfires during these perilous conditions. Nc Weather Bot, Charlotte Observer, 28 Dec. 2025 The plot unfurls 30 years after the Rage Virus spread through England as a boy and his dad travel from the safe harbor of their remote island for a perilous hunting mission. Jeff Spry, Space.com, 27 Dec. 2025 When Alexander is promoted to field work, however, things take a shocking, perilous turn. Aramide Tinubu, Variety, 27 Dec. 2025 Squibb plays Thelma Post, a grandmother who gets duped by a phone scammer, discovers her mistake, and makes a perilous journey through the streets of Los Angeles to track down the culprit. Kevin Jacobsen, Entertainment Weekly, 25 Dec. 2025 See All Example Sentences for perilous

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

Time Traveler
The first known use of perilous was in the 14th century

Browse Nearby Words

Cite this Entry

“Perilous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/perilous. Accessed 31 Dec. 2025.

Kids Definition

perilous

adjective
per·​il·​ous ˈper-ə-ləs How to pronounce perilous (audio)
: full of or involving peril
perilously adverb
perilousness noun

More from Merriam-Webster on perilous

Last Updated: - Updated example sentences
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