bacteria
noun
plural of bacterium
Maanvi SinghNote: Microscopic single-celled organisms lacking a distinct nucleus are known as bacteria. They may be shaped like spheres, rods, or spirals. They inhabit virtually all environments, including soil, water, organic matter, and the bodies of animals. Many bacteria swim by means of long whiplike structures called flagella. The DNA of most bacteria is found in a single, circular chromosome, and is distributed throughout the cytoplasm rather than contained within a membrane-enclosed nucleus. Though some bacteria can cause food poisoning and infectious diseases in humans, most are harmless and many are beneficial. They are used in various industrial processes, especially in the food industry (for example, in the production of yogurt, cheeses, and pickles).
Is bacteria singular or plural?: Usage Guide
In its established and uncontroversial uses, bacteria is the plural of bacterium.
Stephen Jay Gould
In speech and in some, typically nontechnical, journalistic writing, it also occurs in a singular sense, synonymous with bacterium.
The Wall Street Journal
Leah Hardy
Although the singular use of bacteria is often identified as an error to be avoided, it is common in published writing. The plural form bacterias is also seen but is relatively rare.
Allan Bruckheim
Examples of bacteria in a Sentence
Maggie O'Neill, Health, 3 Oct. 2024
PPIs may also be prescribed alongside certain antibiotics to treat a gut infection caused by bacteria known as H. pylori.
—Patricia Weiser, Pharmd, Verywell Health, 2 Oct. 2024
Antimicrobial resistance happens when bacteria, viruses, fungi and other microbes no longer respond to the medicines (antibiotics, antivirals, antifungals) used to treat them.
—World Economic Forum, Forbes, 30 Sep. 2024
Water in a stream, river or lake may look clean, but it can still be filled with bacteria, viruses, and parasites that can result in waterborne diseases, such as cryptosporidiosis or giardiasis.
—Jack Irvin, People.com, 30 Sep. 2024
See all Example Sentences for bacteria 
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Cite this Entry
“Bacteria.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bacteria. Accessed 8 Oct. 2024.
Copy CitationMedical Definition
bacteria
1 of 2plural of bacterium
bacteria
2 of 2 noun
Wall Street JournalCheryl Clark
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