bio·​film ˌbi-(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 Some cereals build looser associations with bacteria, allowing the organisms to form biofilms on their roots. Matthew Hutson, The New Yorker, 6 Feb. 2024 Tiny microbes invisible to the naked human eye initially settle on the wreck’s surface, forming a carpet of cells, called a biofilm. Avery Paxton, Discover Magazine, 26 Dec. 2023 Those accumulations, also known as biofilms, pose a threat to the environment by introducing invasive species and add to shipping costs by increasing drag on ships. IEEE Spectrum, 17 Dec. 2023 By inhibiting biofilm production, SerraDefend helps your body combat potential threats and maintain a healthy microbial balance. Amber Smith, Discover Magazine, 27 June 2023 This biofilm is sandwiched between two mesh electrodes, which transfer the electrons from the biofilm. Miriam Fauzia, Popular Mechanics, 15 Aug. 2022 The goal in brushing focuses on removing the biofilm of plaque from both teeth and gums, not allowing bacteria, fungi and viruses to grow in what is the second-greatest biodiverse home in the human body after the gut. Tim Newcomb, Popular Mechanics, 21 July 2022 This will help prevent the formation of those biofilms. Brittany Anas, House Beautiful, 27 June 2023 Although hospital records indicated that the machines had been maintained and cleaned per the manufacturer's instructions, the researchers noted visible bacterial biofilms on the inside components of the machines. Beth Mole, Ars Technica, 7 Mar. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'biofilm.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1975, in the meaning defined above

Time Traveler
The first known use of biofilm was in 1975

Dictionary Entries Near biofilm

Cite this Entry

“Biofilm.” Dictionary, Merriam-Webster, Accessed 25 Feb. 2024.

Medical Definition


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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