Synonyms of perilous

perilous

adjective

ˈper-ə-ləs 

as in dangerous

involving potential loss or injury

a perilous journey through hostile territory

Synonyms & Similar Words

• dangerous
• hazardous
• risky
• serious
• precarious
• unsafe
• treacherous
• menacing
• threatening
• unhealthy
• grave
• parlous
• grievous
• venturesome
• uncertain
• fatal
• random
• jeopardizing
• unpleasant
• destructive
• detrimental
• harmful
• deadly
• adverse
• bad
• dicey
• lethal
• sickening
• haphazard
• insecure
• chance
• murderous
• injurious
• distressing
• ugly
• pernicious
• fell
• fateful
• dire
• nasty
• malignant
• deleterious
• wicked
• baneful
• evil
• ultrahazardous
• noxious
• inimical
• killer
• hurtful
• mortal
• ill
• baleful
• deathly
• pestilent

Antonyms & Near Antonyms

• safe
• harmless
• innocuous
• innocent
• beneficial
• advantageous
• nonhazardous
• nonthreatening
• good
• unthreatening
• ultrasafe

Synonym Chooser

How is the word perilous distinct from other similar adjectives?

Some common synonyms of perilous are dangerous, hazardous, precarious, and risky. While all these words mean "bringing or involving the chance of loss or injury," perilous strongly implies the immediacy of danger.

perilous mountain roads

When might dangerous be a better fit than perilous?

The words dangerous and perilous are synonyms, but do differ in nuance. Specifically, dangerous applies to something that may cause harm or loss unless dealt with carefully.

soldiers on a dangerous mission

When is it sensible to use hazardous instead of perilous?

The synonyms hazardous and perilous are sometimes interchangeable, but hazardous implies great and continuous risk of harm or failure.

claims that smoking is hazardous to your health

When can precarious be used instead of perilous?

While in some cases nearly identical to perilous, precarious suggests both insecurity and uncertainty.

earned a precarious living by gambling

When would risky be a good substitute for perilous?

In some situations, the words risky and perilous are roughly equivalent. However, risky often applies to a known and accepted danger.

shied away from risky investments

Example Sentences

Recent Examples of perilous

In a chilling twist of fate, in the film’s first location — a zigzagging, vertical staircase aside a dam in Portugal — a close friend of the group experiences a horrifying accident, captured on camera, that underscores just how perilous Storror’s stunts really are. —Adam B. Vary, Variety, 8 Mar. 2025

Our ancestors crossed a vast ocean, strode into the unknown wilderness and carved their fortunes from the rock and soil of a perilous and very dangerous frontier. —NPR, 5 Mar. 2025

From Sailing Ships To The Ocean Liner Before the advent of the ocean liner, transoceanic travel was a perilous endeavor on sailing ships that were at the mercy of the elements. —David Nikel, Forbes, 16 Mar. 2025

The gathering underscored the perilous, uncertain time federal workers across the Kansas City metro – and the country – find themselves in, as Trump moves to gut federal agencies. —Jonathan Shorman, Kansas City Star, 15 Mar. 2025