hazardous

adjective
haz·​ard·​ous | \ˈha-zər-dəs \

Definition of hazardous 

1 : depending on the effect of unpredictable and unanalyzable forces in determining events : depending on hazard (see hazard entry 1 sense 3a) or chance hazardous outcomes

2 : involving or exposing one to risk (as of loss or harm) a hazardous occupation disposing of hazardous waste

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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

Cal-Fire, the state fire-protection agency, has classified more than 180 locales in 31 counties—from Siskiyou on the state’s northern border to San Diego to the south—as being in the most hazardous fire zones. Alejandro Lazo, WSJ, "California Rethinks Firefighting Tactics, Evacuation Routes for Future Wildfires," 30 Nov. 2018 In aviation systems analysis for certification purposes, a hazardous failure must have a probability of no more than one in 10 million. Dominic Gates, The Seattle Times, "Lion Air pilots struggled against Boeing’s 737 MAX flight-control system, black-box data shows," 27 Nov. 2018 Those who endure the hazardous storms that blast extreme planets can seek out precious new crystal treasures that only light up during the worst weather. Andrew Webster, The Verge, "No Man’s Sky’s new update makes its sci-fi worlds even more alien," 21 Nov. 2018 The last several decades have seen a jump in the number of strikes, thanks to a combination of an increase in air travel, the continued growth of populations of animals hazardous to planes, and improved procedures for reporting them. Cynthia Drescher, Condé Nast Traveler, "How Airports Keep Birds Away," 5 Nov. 2018 In Boracay, officials said the situation had deteriorated to such an extent that there were hazardous levels of human feces in the water. Jake Maxwell Watts, WSJ, "Paradise Regained as Boracay Gets Ready to Party On," 26 Oct. 2018 Larger quantities should go into the hazardous waste system. Mike Allen, Popular Mechanics, "How to Dispose of Hazardous Waste Without Damaging the Environment," 9 Oct. 2018 This speed-boosting, trajectory-altering flyby would steer the spacecraft-asteroid combo toward the hazardous object. Mike Wall, Space.com, "Asteroid Billiards: This Wild Idea to Protect Earth Just Might Work," 24 Aug. 2018 The Dangers of Using Vinegar in Your Garden In concentrations this strong, vinegar becomes hazardous and can cause environmental damage. Margaret Roach, Good Housekeeping, "Why It Can Be Dangerous to Use Vinegar to Kill Weeds," 15 Aug. 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 2

History and Etymology for hazardous

see hazard entry 1

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Statistics for hazardous

Last Updated

14 Dec 2018

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 \

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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