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

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 companies occupying the space had been previously cited for fire code and hazardous materials violations before the fire. Christian Martinezstaff Writer, Los Angeles Times, 15 July 2022 Moreover, when a nuclear reactor of any size reaches the end of its useful life, the cost of storing the hazardous waste extends far into the future. Rick Barrett, Milwaukee Journal Sentinel, 19 May 2022 Evacuees can find more information on safety protocols and indications of how to dispose of hazardous waste and spoiled food upon returning by visiting https://www.coconino.az.gov/2900/Re-Entry-Information. Angela Cordoba Perez, The Arizona Republic, 1 May 2022 Absolutely no items containing hazardous waste, such as gasoline in lawn mowers, will be accepted unless the waste has been removed. Laura Groch, San Diego Union-Tribune, 1 May 2022 The facilities in the TRI are usually quite large and deal in electricity, metals, mining, chemicals, or hazardous waste. Zachary Smith, cleveland, 19 Apr. 2022 The energy department also is working on a solution to safely and permanently store the hazardous radioactive waste that is produced from nuclear power. Sarah Bowman, The Indianapolis Star, 24 Jan. 2022 Hahnemann’s doors closed in 2019, and by late 2020 its medical records had been transferred, its signs removed and most of its hazardous biomedical waste handled—except for the pacemaker. Becky Yerak, WSJ, 17 Jan. 2022 The stations typically would accept household garbage, yard debris and hazardous waste from the general public. oregonlive, 15 Jan. 2022 See More

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.

First Known Use of hazardous

1549, in the meaning defined at sense 1

History and Etymology for hazardous

see hazard entry 1

Learn More About hazardous

Time Traveler for hazardous

Time Traveler

The first known use of hazardous was in 1549

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Dictionary Entries Near hazardous

hazard lights


hazard pay

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Statistics for hazardous

Last Updated

4 Aug 2022

Cite this Entry

“Hazardous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hazardous. Accessed 8 Aug. 2022.

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More Definitions for hazardous


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

Kids Definition of hazardous

: dangerous sense 1 hazardous chemicals



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

More from Merriam-Webster on hazardous

Nglish: Translation of hazardous for Spanish Speakers

Britannica English: Translation of hazardous for Arabic Speakers


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