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Showing results for perilous. Search instead for perisoreus.
Synonyms

perilous

American  
[per-uh-luhs] / ˈpɛr ə ləs /

adjective

  1. involving or full of grave risk or peril; hazardous; dangerous.

    a perilous voyage across the Atlantic in a small boat.

    Synonyms:
    risky
    Antonyms:
    safe

perilous British  
/ ˈpɛrɪləs /

adjective

  1. very hazardous or dangerous

    a perilous journey

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • nonperilous adjective
  • perilously adverb
  • perilousness noun
  • unperilous adjective

Etymology

Origin of perilous

First recorded in 1250–1300; Middle English, from Anglo-French perillous, from Latin perīculōsus; see peril, -ous

Explanation

Something that is dangerous or very risky can be described with the adjective perilous. If you are driving in a blizzard, you may kick yourself for making such a perilous journey. The adjective perilous comes from the Latin word periculum, meaning dangerous. Words from the same root include peril, a noun meaning a dangerous situation, and imperil, a verb meaning to put in danger. The last thing you want to do as a parent is to imperil your children. Unfortunately, childhood is filled with peril — from climbing on the monkey bars to eating paste, dirt, or bugs. If you think you can prevent all perilous situations, you haven't been a parent very long!

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Vocabulary lists containing perilous

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The minutes-long standstill forced several people into the street; many more, including my husband and his cane, engaged in a potentially perilous stutter-step around the two knee-high, randomly moving yet noncommunicative vehicles.

From Los Angeles Times • Apr. 14, 2026

That said, relying on a future inheritance is a perilous strategy for compensation.

From MarketWatch • Mar. 30, 2026

The World Health Organisation said that the conflict was at a "perilous stage" and called for restraint.

From BBC • Mar. 24, 2026

"The war in the Middle East has reached a perilous stage" with the strikes on Natanz and Dimona, WHO chief Tedros Adhanom Ghebreyesus said on X.

From Barron's • Mar. 22, 2026

When he turned from her he had for a moment a perilous sense of ease and freedom, which was more acute because he knew that soon it was to be shattered.

From "The Heart is a Lonely Hunter" by Carson McCullers