hazardous

adjective

haz·​ard·​ous ˈha-zər-dəs 

1

: involving or exposing one to risk (as of loss or harm)

a hazardous occupation

disposing of hazardous waste

2

: depending on the effect of unpredictable and unanalyzable forces in determining events : depending on hazard (see hazard entry 1 sense 2a) or chance

hazardous outcomes

hazardously adverb

hazardousness noun

Synonyms

• dangerous
• grave
• grievous
• jeopardizing
• menacing
• parlous
• perilous
• risky
• serious
• threatening
• unhealthy
• unsafe
• venturesome

Choose the Right Synonym for hazardous

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 hazardous in a Sentence

It was a hazardous voyage.

These are hazardous chemicals that can cause death if inhaled.

Recent Examples on the Web

Public housing residents have also raised concerns about hazardous conditions inside Housing Authority buildings — including mold, gun violence, and rodent and bug infestations. —Sarah Volpenhein, Journal Sentinel, 8 Dec. 2024

The search was delayed for three days due to hazardous conditions. —Daniel R. Depetris, Newsweek, 6 Dec. 2024

Here's where and what to know Difficult travel is also expected in that region, along with hazardous conditions during the Thursday morning and evening commutes. —Tanya Wildt, Detroit Free Press, 6 Dec. 2024

The hazardous conditions could impact the Friday evening commute, the NWS said. —Keith Matheny, USA TODAY, 6 Dec. 2024

Word History

Etymology

see hazard entry 1

First Known Use

1549, in the meaning defined at sense 1

Kids Definition

hazardous

adjective

haz·​ard·​ous ˈhaz-ərd-əs 

: dangerous sense 1, risky

hazardously adverb

hazardousness noun

Legal Definition

hazardous

adjective

haz·​ard·​ous

: creating a hazard : involving or exposing one to risk (as of loss or harm)

a hazardous occupation

a hazardous substance

hazardously adverb