hazardous

adjective
haz·​ard·​ous | \ ˈha-zər-dəs How to pronounce hazardous (audio) \

Definition of hazardous

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

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Other Words from hazardous

hazardously adverb
hazardousness noun

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

The robots accomplish the job without endangering humans in the potentially hazardous process. Kyle Mizokami, Popular Mechanics, "The Army Is Using Robots to Dismantle Hazardous Rockets," 26 Feb. 2019 Nayeb worked in the vehicle yard, disposing of motor oil and other potentially hazardous automotive materials. Russ Bynum, The Seattle Times, "US soldier wounded in suicide attack sues bomber’s employer," 20 Feb. 2019 In the case of the device sent to CNN, the NYPD and the FBI must work around potentially hazardous white powder that was also in the package. Zolan Kanno-youngs, WSJ, "NYPD’s ‘Total Containment Vessel’ Takes CNN Bomb Away," 24 Oct. 2018 More than a dozen such Superfund sites in and around Houston flooded last year in the aftermath of Hurricane Harvey, with spills of potentially hazardous materials reported at two. Michael Biesecker, Fox News, "Hurricane could flood many waste sites, creating toxic brew," 12 Sep. 2018 However, all tenants evacuated the complex in October 2016 because of the discovery of potentially hazardous fumes still lingering in the air. Detroit Free Press, "Ford would demolish this vacant Detroit building," 21 June 2018 Those predicted to pass within about 4.6 million miles of Earth -- less than 19.5 times the Earth-moon distance -- are known as potentially hazardous asteroids, or PHAs. William Harwood, CBS News, "NASA asteroid-watchers team up on emergency plan with White House, FEMA," 20 June 2018 The list of policies targeted by the EPA under Pruitt includes everything from repealing the Clean Power Plan, the chief Obama-era measure aimed at fighting climate change, to reversing a ban on chlorpyrifos, a potentially hazardous pesticide. Justin Worland, Time, "EPA Head Scott Pruitt Has Been Embroiled in Scandals. Here's How He's Survived," 24 Apr. 2018 Parata is a Ngātiwai environmental resource manager, and for him a dead whale on a beach isn’t just a smelly and potentially hazardous mess. National Geographic, "This Man Has Helped Give 460 Dead Whales a Second Life—As Art," 9 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hazardous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of hazardous

1549, in the meaning defined at sense 1

History and Etymology for hazardous

see hazard entry 1

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Statistics for hazardous

Last Updated

18 May 2019

Look-up Popularity

Time Traveler for hazardous

The first known use of hazardous was in 1549

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More Definitions for hazardous

hazardous

adjective

English Language Learners Definition of hazardous

: involving risk or danger

hazardous

adjective
haz·​ard·​ous | \ ˈha-zər-dəs How to pronounce hazardous (audio) \

Kids Definition of hazardous

: dangerous sense 1 hazardous chemicals

hazardous

adjective
haz·​ard·​ous

Legal Definition of hazardous

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

Other Words from hazardous

hazardously adverb

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Comments on hazardous

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