bio·​film | \ ˌbi-(ˌ)ō-ˈfilm How to pronounce biofilm (audio) \

Definition of biofilm

: a thin usually resistant layer of microorganisms (such as bacteria) that form on and coat various surfaces

Examples of biofilm in a Sentence

Recent Examples on the Web As Lefrak writes, the Park Service is currently conducting an $8.75 million restoration effort to repair the memorial’s internal roofing structure and remove black biofilm that began growing on the marble dome in 2010. Jason Daley, Smithsonian, "Philanthropist Donates $10 Million to Jefferson Memorial Museum," 1 Nov. 2019 The bacteria that normally reside in the mouth grow as dental plaque, a biofilm that firmly attaches to teeth and oral surfaces such as the tongue. Frank Scannapieco, The Conversation, "Lack of toothbrushing for seniors in nursing homes may sound gross, but it’s a serious health risk," 17 Sep. 2019 In an additional feeding experiment, the researchers placed the microbeads in seawater to cover them with a biofilm—a thin layer of bacteria. Jenny Howard, National Geographic, "These corals choose to eat plastic over food," 25 June 2019 Then the biofilms would stop expanding until the glutamate was replenished. Quanta Magazine, "Bacteria Use Brainlike Bursts of Electricity to Communicate," 5 Sep. 2017 And the researchers indicate that things could be even better, as phages can be engineered to carry enzymes that make the bacteria even more vulnerable (by digesting biofilms, as one example). John Timmer, Ars Technica, "Using a virus to kill what antibiotics can’t," 18 July 2018 The treatment worked in culture dishes and when the bacteria were given the chance to form a biofilm, a dense, three-dimensional mesh that can protect bacteria from drugs. John Timmer, Ars Technica, "Using a virus to kill what antibiotics can’t," 18 July 2018 These slimy biofilms typically have to be scrubbed off. NBC News, "Hard-to-kill germs may be lurking in your hotel pool, CDC says," 17 May 2018 To really break up the biofilms in a home, Tierno recommends scrubbing surfaces with a metal brush, soap, and water, and a 10 percent bleach solution when it's really needed. Sarah Gibbens, National Geographic, "What to Know About the Germs in Your Home," 3 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'biofilm.' 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 biofilm

1975, in the meaning defined above

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Time Traveler for biofilm

Time Traveler

The first known use of biofilm was in 1975

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Cite this Entry

“Biofilm.” The Dictionary, Merriam-Webster Inc., Accessed 25 January 2020.

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More Definitions for biofilm


bio·​film | \ ˈbī-ō-ˌfilm How to pronounce biofilm (audio) \

Medical Definition of biofilm

: a thin usually resistant layer of microorganisms (as bacteria) that form on and coat various surfaces (as of catheters or water pipes)

Comments on biofilm

What made you want to look up biofilm? Please tell us where you read or heard it (including the quote, if possible).


dull or mediocre

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