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.
Imani Lamour, who lives near the Chew Avenue home in Olney, stopped to watch investigators in hazmat suits move through the property. — Joe Brandt, CBS News, 28 Sep. 2026 Calls often include car accidents, search and rescue, downed power lines from storms, hazmat issues, medical incidents, animals caught in trees and beeping smoke detectors. — Julia Levine, Hartford Courant, 7 Sep. 2026 No one is going to want to touch you and your chunder without throwing on a hazmat suit first. — Austin Perry Outkick, FOXNews.com, 5 Sep. 2026 Workers in white hazmat suits unload bodies from a stream of ambulances. — Surendra Phuyal, NBC news, 1 Sep. 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 9 Oct. 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 suits—Tom Spousta
hazmat storage
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