often attributive
: a material (such as flammable or poisonous material) that would be a danger to life or to the environment if released without precautions

Did you know?

The origin of "hazmat" is clear enough - it was formed by combining the first three letters of each of two words: "hazardous" and "material." The word hazmat is fairly young, first appearing in print in 1980. Although it is a noun, "hazmat" tends to be used attributively, meaning that it often appears in sentences before another noun as if it were performing the duties of an adjective (as in "hazmat team" and "hazmat worker").

Examples of hazmat in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Workers in white hazmat suits unload bodies from a stream of ambulances. Surendra Phuyal, NBC news, 1 Sep. 2026 Those who collected evidence had to use hazmat suits and gas masks while inside the home. Andrea May Sahouri, Freep.com, 1 Sep. 2026 In addition to the $100-million reimbursement program announced Monday, the office is seeking reimbursement for emergency services agencies that responded to the crisis as well as civil penalties related to the hazmat situation. Clara Harter, Los Angeles Times, 24 Aug. 2026 Police are directing traffic and the Grand Prairie hazmat unit is on the scene after at least 10 railcars derailed in Mansfield on Thursday evening, officials said. S.e. Jenkins, CBS News, 20 Aug. 2026 See All Example Sentences for hazmat

Word History

Etymology

hazardous material

First Known Use

1972, in the meaning defined above

Time Traveler
The first known use of hazmat was in 1972

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Cite this Entry

“Hazmat.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hazmat. Accessed 5 Sep. 2026.

Medical Definition

hazmat

noun
haz·​mat
ˈhaz-ˌmat
often attributive
: a material (as radioactive, flammable, explosive, or poisonous material) that would be a danger to life or to the environment if released without necessary precautions being taken
toxic waste hauled away by workers in hazmat suitsTom Spousta
hazmat storage
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