hazardous

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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 ¹hazard 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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hazardously

adverb

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hazardousness

noun

See hazardous defined for English-language learners

See hazardous defined for kids

Examples of hazardous in a Sentence

It was a hazardous voyage.
These are hazardous chemicals that can cause death if inhaled.

Recent Examples of hazardous from the Web

Hazardous waste, electronics and unwanted items can be recycled and reused at Recyclepalooza, hosted by ShareFest New Lenox, 8 a.m. to 3 p.m. Sept. 9 at the Spencer School campus, 1701 Spencer Road, New Lenox.

— susan demar lafferty, Daily Southtown, "Recyclepalooza event Sept. 9 in New Lenox," 30 Aug. 2017
Houston's opener at UTSA, which was scheduled for Saturday, has been postponed due to hazardous weather conditions caused by Hurricane Harvey, the school announced on Tuesday.

— daniel rapaport, SI.com, "Houston vs. UTSA Postponed Due to Hurricane Harvey," 29 Aug. 2017
The company also would still need a federal Clean Water Act permit to discharge wastewater and would have to abide by air quality and hazardous waste standards through permits.

— ivan moreno, chicagotribune.com, "What are the environmental concerns surrounding the Wisconsin Foxconn plant?," 26 Aug. 2017
Highs on Sunday were expected to be in the lower to mid 90s, but the heat index could climb to 100 degrees, which could be hazardous to those without power.

— robert a. cronkleton and joe robertson, kansascity, "Damaging storms leave tens of thousands without power in the Kansas City area," 23 July 2017
A private facility in Colfax, 95 miles south, operated by Clean Harbors, a longtime Defense Department contractor and one of the largest hazardous waste handlers in North America.

— charles p. pierce, Esquire, "The Roots of Injustice in Colfax, Louisiana, Go Very Deep," 21 July 2017
The residue from the burning piles rises in a spindle of hazardous smoke, twists into the wind and, depending on the weather, sweeps toward the tens of thousands of residents in the surrounding towns.

— krista stevens, Longreads, "Open Burning: A Banned Practice That’s Poisoning America," 21 July 2017
The hazardous weather alert announced dangerously high temperatures as heat and humidity build across the region.

— mariel padilla, Cincinnati.com, "Heat wave to hit Cincinnati this week," 18 July 2017
Although the EPA has maintained that the site is minimally hazardous, some residents have formed advocacy groups to raise awareness and demand immediate removal of the waste.

— danielle jackson, Longreads, "The St. Louis Suburbs Bear the Cost of America’s Nuclear Past," 15 July 2017

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.

Origin and Etymology of hazardous

see ¹hazard

NEW! Time Traveler

First Known Use: 1585

See Words from the same year

hazardous Synonyms

Near Antonyms

advantageous, beneficial, good; ultrasafe

Synonym Discussion of 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

HAZARDOUS Defined for English Language Learners

hazardous

play

adjective

Definition of hazardous for English Language Learners

: involving risk or danger

HAZARDOUS Defined for Kids

hazardous

play

adjective haz·ard·ous \ ˈha-zər-dəs \

Definition of hazardous for Students

:dangerous 1 hazardous chemicals

Law Dictionary

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

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hazardously

adverb

Learn More about hazardous

Thesaurus: All synonyms and antonyms for hazardous Spanish Central: Translation of hazardous Nglish: Translation of hazardous for Spanish speakers Britannica English: Translation of hazardous for Arabic speakers

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