biofilm

noun

bio·​film ˌbī-(ˌ)ō-ˈfilm How to pronounce biofilm (audio)
: 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
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.
The black goo biofilm can be cleaned off with minimal effort. — Tim Carter, Hartford Courant, 6 June 2026 Your shower can look clean but still harbor bacteria, mold, and biofilm, which thrive in moist environments. — Rae Ford, Martha Stewart, 10 May 2026 Brushing and flossing regularly can help people remove the biofilm, or plaque, from teeth and keep it from hardening into tartar. — Anne Ewbank, Popular Science, 22 Apr. 2026 Water bowls should also be cleaned every day, since saliva and bacteria can quickly create the slippery layer called biofilm that many owners notice around the edges. — Usa Today, USA Today, 10 June 2026 See All Example Sentences for biofilm

Word History

First Known Use

1975, in the meaning defined above

Time Traveler
The first known use of biofilm was in 1975

Rhymes for biofilm

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Browse Nearby Words

biofeedback
biofilm
biofilter
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Cite this Entry

“Biofilm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/biofilm. Accessed 8 Jul. 2026.

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Medical Definition

biofilm

noun
bio·​film ˈbī-ō-ˌfilm How to pronounce biofilm (audio)
: a thin usually resistant layer of microorganisms (as bacteria) that form on and coat various surfaces (as of catheters or water pipes)
Last Updated: - Updated example sentences
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