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

These bacteria play a major role in maintaining homeostasis at all layers. Steven Macari, Harper's BAZAAR, "Could a Shower Filter Be the Missing Component to Your Wellness Routine?," 1 May 2019 But Legionella bacteria can survive in water up to 140 degrees. John O'connor, The Seattle Times, "Audit: Slow Legionnaires’ response at Illinois veterans home," 25 Mar. 2019 Vibrio bacteria pose little threat to healthy people who go in the water. Tom Avril, Philly.com, "N.J. man infected with flesh-eating bacteria while crabbing, could lose limbs," 10 July 2018 About 10 million bacteria can set up shop in a square inch of a sponge, with E. coli topping the pecking order and Salmonella not far behind. Ana Veciana-suarez, miamiherald, "A simple Google search turned me into a germophobe," 2 July 2018 When tissue is injured, bacteria move in and begin to degrade that tissue. Julie Mazziotta, PEOPLE.com, "What to Know About Necrosis, the Deadly Disease That Made a Man Smell So Bad His Plane Had an Emergency Landing," 28 June 2018 Microorganisms flourish at the bottom of the cold sea and in the vents of boiling hot springs; bacteria can even survive in radioactive waste. Jason Pontin, WIRED, "The 19th-Century Crank Who Tried to Tell Us About the Microbiome," 15 June 2018 But until now, researchers thought these bacteria could absorb only specific, higher-energy wavelengths of light. Sarah Lewin, Space.com, "Weird Low-Light Bacteria Could Potentially Thrive on Mars," 15 June 2018 If bacteria also infect the bloodstream (called septicemic plague) or the lungs (called pneumonic plague), organ failure and death can occur if it’s not treated right away. Amanda Macmillan, Health.com, "An Idaho Child Was Diagnosed With the Plague. How Worried Should You Be?," 13 June 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

15 May 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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