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

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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 Maggie and Knoblauch's work has earned the Coroner's Office the first-ever grant for a cadaver dog from Aftermath, a company that specializes in biohazard cleanup, including crime scenes. Sara Pagones | Staff Writer,, "Maggie puts her nose to the grindstone as investigator with St. Tammany Parish Coroner's Office," 11 Jan. 2021 Back in Ingende Hospital, the doctors are wearing as much protective gear as can be found: Goggles, yellow biohazard overalls, double gloves taped shut, hoods over their heads and shoulders, galoshes over their shoes, and complex facemasks. Sam Kiley, CNN, "In the Congo rainforest, the doctor who discovered Ebola warns of deadly viruses yet to come," 22 Dec. 2020 Besides a few biohazard signs and specialized ventilation systems that keep laboratory air inside the lab, these spaces would look familiar to any biology student. Rebecca Renner, Science, "How scientists plan to protect Earth from extraterrestrial germs," 11 Dec. 2020 Hire additional staff to focus efforts on biohazard cleanup. Jessica Boehm, The Arizona Republic, "'Stepping up to do more': Phoenix council approves broad plan to address homelessness, affordable housing," 27 May 2020 Once the plastic sticks, one for each sample, are retracted and sealed in a bag marked 'biohazard', the residents are hustled out of the facility. Eamon Barrett, Fortune, "Hong Kong’s citywide COVID-19 testing has become a barometer of public trust," 9 Sep. 2020 The deputies restraining her wore biohazard gear, plausibly sufficient protection from the dangers of spittle. Tasha Williams, The New Republic, "The American Horror of Hooding," 5 Sep. 2020 The vaccine itself was stored in a locked room marked with biohazard safety posters. Austen Erblat,, "COVID-19 vaccine trial kicks off in Palm Beach County. Volunteers will get up to $1,000.," 17 Aug. 2020 Starting up these systems would require clearing logistical and regulatory hurdles—a positive coronavirus sample is a low-level biohazard, and the FDA regulates it as such. Robinson Meyer, The Atlantic, "The Way Out," 14 Aug. 2020

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.

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First Known Use of biohazard

1965, in the meaning defined above

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Time Traveler for biohazard

Time Traveler

The first known use of biohazard was in 1965

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Statistics for biohazard

Last Updated

25 Jan 2021

Cite this Entry

“Biohazard.” Dictionary, Merriam-Webster, Accessed 27 Jan. 2021.

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More Definitions for biohazard


How to pronounce biohazard (audio)

English Language Learners Definition of biohazard

: a biological or chemical substance or situation that is dangerous to human beings and the environment


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

Comments on biohazard

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