perilous

adjective

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

Synonyms of perilous

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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 as evidenced by Spade and the D’Allara family's reunion, the emotional connections fostered on that perilous day have persisted through two decades. — Kalia Richardson, USA Today, 22 Aug. 2026 Matt Damon stars as Odysseus, the Greek king attempting to make his perilous journey home to Ithaca after the Trojan War. — Anna Tingley, Variety, 21 Aug. 2026 This is not an unfamiliar setting for Foster, 44, who was a math teacher in Ghana before making the perilous journey through the Sahel toward Libya, and then across the Mediterranean into Italy, finally arriving in Spain. — Vasco Cotovio, CNN Money, 21 Aug. 2026 Twain was inspired to publish the ambitious Library of American Literature with 1,700 selections by 500 authors in eleven volumes, but failed to grasp the perilous economics of selling such a gargantuan series by subscription. — Literary Hub, 21 Aug. 2026 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

Rhymes for perilous

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Browse Nearby Words

perilless
perilous
perilously
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Cite this Entry

“Perilous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/perilous. Accessed 1 Sep. 2026.

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Kids Definition

perilous

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