perilous

adjective

per·​il·​ous ˈper-ə-ləs How to pronounce perilous (audio)
ˈpe-rə-
: 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.
And staffing struggles continue to strain the agencies tasked with policing perilous road behavior. Fort Worth Star-Telegram, 10 July 2025 To a Washington bean counter, his loss might have looked like one tiny but welcome subtraction in a giant spreadsheet, but not in a region so prone to these perilous events that it’s known as Flash Flood Alley. Zeynep Tufekci, Mercury News, 10 July 2025 Brown, like Espada, is often put in perilous predicaments while trying to discuss any of these developments. Chandler Rome, New York Times, 10 July 2025 Understanding the gravity of a red flag warning and adhering to these precautions is pivotal in mitigating the risk of wildfires during these perilous conditions. Ca Weather Bot, Sacbee.com, 30 June 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 21 Jul. 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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