perilous

1 of 2

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

perilousness

2 of 2

noun

per·​il·​ous·​ness
plural -es
: the quality or state of being perilous

Synonyms of perilous

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Adjective

See All Synonyms & Antonyms in Thesaurus
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

Adjective a perilous journey across the mountains a perilous journey through hostile territory
Recent Examples on the Web
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Adjective
Christopher Nolan’s recent film reminded me of another time when the world was awash in ambiguity and leaders needed to navigate the perilous voyage across unfamiliar territory. — Jeff Degraff, Fortune, 17 Oct. 2026 Two Utah residents who hiked Mount Shasta in Northern California were rescued after they became stranded during a perilous 36-hour journey through freezing conditions. — Tony Briscoe, Los Angeles Times, 17 Oct. 2026 That willingness to take risks extended to campaigning for Jessie and Buzz to kiss amid a perilous action sequence. — Davide Abbatescianni, Variety, 16 Oct. 2026 Regardless, transiting the Strait remains a perilous endeavor for commercial ships. — Lim Hui Jie, CNBC, 15 Oct. 2026 See All Example Sentences for perilous

Word History

Etymology

Adjective

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

Adjective

14th century, in the meaning defined above

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

Rhymes for perilous

See All Rhymes for perilous

Browse Nearby Words

perilless
perilous
perilously
See all Nearby Words

Cite this Entry

“Perilous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/perilous. Accessed 22 Oct. 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
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