bio·​haz·​ard | \ ˈbī-ō-ˌha-zərd How to pronounce biohazard (audio) \

Definition of biohazard

: a biological agent or condition that is a hazard to humans or the environment also : a hazard posed by such an agent or condition

Other Words from biohazard

biohazardous \ ˌbī-​ō-​ˈha-​zər-​dəs \ adjective

Examples of biohazard in a Sentence

The gasoline spill created a serious biohazard.
Recent Examples on the Web The mass spec machine identifies a biohazard and goes into automatic lockdown with Kasie and Palmer inside her lab. Sara Netzley,, 1 Mar. 2022 In any event, what was at first a minor inconvenience that would eventually decay or be kicked into the brush is now a biohazard that will last dozens or hundreds of years. Outside Online, 16 Feb. 2022 Opponents say the process ignores both culture and nature, and could be scientifically risky, creating potential allergens and untested byproducts, along with waste that might be a biohazard. New York Times, 15 Feb. 2022 Erik Bordi took in a grim scene: five biohazard cans, two refrigeration containers stacked with human remains, a gurney ready to load in a truck. Rachel Swan, San Francisco Chronicle, 8 Feb. 2022 One of them, a biohazard symbol, is associated with HIV-positive individuals. Daniel Funke, USA TODAY, 26 Apr. 2017 Your dental hygienist still dresses like a biohazard worker. Kirkland Crawford, Detroit Free Press, 15 Nov. 2021 Some logistical concerns raised by the city are still being negotiated, such as the disposal of biohazard waste and how to handle ambulance pickups involving obese people. David Garrick, San Diego Union-Tribune, 20 Oct. 2021 Not accepted are liquids, ointments, lotions, aerosols, personal care products, hydrogen peroxide or alcohol, thermometers, biohazard or infectious waste, and food items. Jennifer Johnson,, 19 Oct. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'biohazard.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of biohazard

1965, in the meaning defined above

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The first known use of biohazard was in 1965

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Cite this Entry

“Biohazard.” Dictionary, Merriam-Webster, Accessed 23 May. 2022.

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More Definitions for biohazard


bio·​haz·​ard | \ ˈbī-ō-ˌhaz-ərd, -ˈhaz- How to pronounce biohazard (audio) \

Medical Definition of biohazard

: a biological agent or condition (as an infectious organism or insecure laboratory procedures) that constitutes a hazard to humans or the environment also : a hazard posed by such an agent or condition

Other Words from biohazard

biohazardous \ -​ˈhaz-​ərd-​əs How to pronounce biohazard (audio) \ adjective


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