Plural word for bacteria Bacteria is the plural form of the singular bacterium. Because microscopic bacterium is most often found in multiples, the plural form bacteria is more commonly used. The plurals of several other singular words ending in -um are also formed this way, such as memorandum/memoranda and curriculum/curricula. The irregular noun bacterium’s plural derives directly from its original pluralization in Latin and Greek. Bacteria is sometimes treated as a singular collective noun. However, this is not standard in English, and bacteria should be treated as a plural form.
Some bacteria are beneficial to humans (for example, those that live in the stomach and aid digestion), and some are harmful (for example, those that cause disease).
First recorded in 1860–65; from New Latin, from Greek baktḗria, plural of baktḗrion, diminutive of baktēría “staff, cane”; see origin at bacterium
First recorded in 1860–65; from New Latin; see origin at bacteria ( def. )
Bacteria are microscopic living organisms, usually one-celled, that can be found everywhere. They can be dangerous, such as when they cause infection, or beneficial, as in the process of fermentation (such as in wine) and that of decomposition. In 1676, Anton Van Leeuwenhoek first observed bacteria through a microscope and called them “animalcules.” In 1838, the German Naturalist Christian Gottfried Ehrenberg called them bacteria, from the Greek baktḗria, meaning "little stick." An apt word, as the first observed bacteria were shaped like rods, although bacteria can also be spiral or spherical in shape. A grammar note: The word bacteria is the plural form of "bacterium" and so should be written as plural, as in "Many bacteria are harmless."
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The compound, known as DT-109, works by reducing harmful gut bacteria, protecting the intestinal lining, and preventing inflammatory substances from reaching the liver.
From Science Daily ● Oct. 17, 2026
Some polymers contain bonds that microbial enzymes can attack, allowing bacteria to dismantle them into smaller molecules.
From Science Daily ● Oct. 16, 2026
This sleight of hand, Mr. Silvertown explains, was first performed by aquatic bacteria more than three billion years ago.
From The Wall Street Journal ● Oct. 16, 2026
Researchers at the University of Konstanz have now discovered an unusual enzyme that could reveal how some bacteria are becoming better equipped to break down certain types of plastic.
From Science Daily ● Oct. 16, 2026
The highly contagious illness is caused by bacteria growing in the body, usually the lungs, and is spread through the air when people cough, sneeze, or spit.
From "At Last She Stood" by Erin Entrada Kelly
Bacteria in treated trees have dropped by at least 90%.
From The Wall Street Journal ● Sep. 19, 2026
Bacteria found in soil and water are essential parts of natural ecosystems, and some species are capable of processing substances that can be harmful to humans and other organisms.
From Science Daily ● Aug. 9, 2026
Bacteria can also infect wounds where screwworm maggots are present and may cause an infection that can lead to symptoms like fever or chills.
From Los Angeles Times ● Jun. 6, 2026
Bacteria evolve quickly, and that adaptability is fueling a growing public health crisis.
From Science Daily ● Feb. 28, 2026
Bacteria have a lot more to do than viruses.
From "Cosmos" by Carl Sagan
Before examining the drug's effects, the scientists confirmed an important contributor to MASH: excessive growth of Clostridium perfringens, a bacterium that produces ammonia inside the intestines.
From Science Daily ● Oct. 17, 2026
Plague is a disease caused by the Yersinia pestis bacterium, the same pathogen that killed millions of people in Europe during the Middle Ages.
From Barron's ● Oct. 7, 2026
The bacterium that causes the plague, Yersinia pestis, found among rodents such as marmots in the area.
From BBC ● Oct. 7, 2026
The bacterium Yersinia pestis, which can cause pneumonic and bubonic plagues, has been identified from time to time in Siberia, linked to exposure to vermin.
From The Wall Street Journal ● Oct. 5, 2026
At least for a while, though, as long as the patient is still alive, the cholera bacterium profits from being massively broadcast into the water supplies of its next victims.
From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond
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