bacteria

noun
bac·​te·​ria | \ bak-ˈtir-ē-ə How to pronounce bacteria (audio) \
plural bacteria also bacterias

Definition of bacteria

: bacterium not usually used technically

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Is bacteria singular or plural?: Usage Guide

Bacteria is regularly a plural in scientific and pedagogical use; in speech and in journalism it is also used as a singular, and it is sometimes pluralized as bacterias. caused by a bacteria borne by certain tiny ticks Wall Street Journal more resistant to chlorine and elevated water temperatures than other bacterias — Allan Bruckheim, M.D., Chicago Tribune These journalistic uses are found in British as well as American sources.

Did You Know?

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 whip-like 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).

Examples of bacteria in a Sentence

Recent Examples on the Web

But the majority of proteins—between 85 and 95 percent—had been produced by bacteria from the microbiome. Kiona N. Smith, Ars Technica, "Medieval dental plaque sheds light on how our microbiomes have changed," 25 Nov. 2018 Pound for pound — or nanogram for nanogram, as is the case — the neurotoxin botulinum, produced by bacteria, is the deadliest substance known. Gemma Tarlach, Discover Magazine, "20 Things You Didn't Know About ... Poison," 25 Sep. 2018 Acne is caused, in part, by P. acnes bacteria that are with you your whole life. Elizabeth Siegel, Allure, "Doctors Are Working on an Acne Vaccine — Here's Everything We Know So Far," 31 Aug. 2018 While facial acne usually forms due to a collection of oil and debris, vaginal acne is caused by an infection due to bacteria that forms around your pubic hair follicles, Dr. Bhuyan says. Yerin Kim, Seventeen, "What Is Vaginal Acne, and How Do You Treat It?," 3 Dec. 2018 There’s helpful inflammation, as when your body’s immune system mounts a response to bacteria in a cut. Eliza Barclay, Vox, "The growth of yoga and meditation in the US since 2012 is remarkable," 11 Nov. 2018 Public Health — Seattle & King County monitors bacteria levels on a weekly basis. Sarah Wu, The Seattle Times, "Kirkland closes popular Juanita beach due to sewage pollution," 28 July 2018 Areas like the kitchen sink and objects such as the cutting board are prone to more bacteria than the toilet bowl. Nicole Spector /, NBC News, "The kitchen is the germiest room. Here's how to deep clean everything.," 3 July 2018 This helps eliminate risk of anaerobic bacteria growth. Bonnie S. Benwick, charlotteobserver, "What you should know about buying frozen fish," 3 July 2018

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

1864, in the meaning defined above

History and Etymology for bacteria

plural of bacterium

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Statistics for bacteria

Last Updated

6 Mar 2019

Look-up Popularity

Time Traveler for bacteria

The first known use of bacteria was in 1864

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More Definitions for bacteria

bacteria

Medical Definition of bacteria

 (Entry 1 of 2)

plural of bacterium

bacteria

noun
bac·​te·​ria | \ bak-ˈtir-ē-ə How to pronounce bacteria (audio) \

Medical Definition of bacteria (Entry 2 of 2)

1 : bacterium not usually used technically caused by a bacteria borne by certain tiny ticksWall Street Journal a single bacteria—there are roughly 200 in each cough—apparently can infect a person— Cheryl Clark
2  plural capitalized : a domain in the system of classification dividing all organisms into three major domains of life that includes the prokaryotes that are bacteria but not those that are archaebacteria or archaea — compare eubacteria

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More from Merriam-Webster on bacteria

Rhyming Dictionary: Words that rhyme with bacteria

Spanish Central: Translation of bacteria

Nglish: Translation of bacteria for Spanish Speakers

Britannica English: Translation of bacteria for Arabic Speakers

Britannica.com: Encyclopedia article about bacteria

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