Definitions for bacteria
bækˈtɪər i ə; -ˈtɪər i əmbac·te·ri·a

Princeton's WordNetRate this definition:3.0 / 4 votes

1. bacteria, bacteriumnoun

   (microbiology) single-celled or noncellular spherical or spiral or rod-shaped organisms lacking chlorophyll that reproduce by fission; important as pathogens and for biochemical properties; taxonomy is difficult; often considered to be plants

WiktionaryRate this definition:2.0 / 2 votes

1. bacterianoun

   Plural form of bacterium.

WikipediaRate this definition:0.0 / 0 votes

1. Bacteria

   Bacteria ( (listen); singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationships with plants and animals. Most bacteria have not been characterised and there are many species that cannot be grown in the laboratory. The study of bacteria is known as bacteriology, a branch of microbiology. Humans and most other animals carry millions of bacteria. Most are in the gut, and there are many on the skin. Most of the bacteria in and on the body are harmless or rendered so by the protective effects of the immune system, and many are beneficial, particularly the ones in the gut. However, several species of bacteria are pathogenic and cause infectious diseases, including cholera, syphilis, anthrax, leprosy, tuberculosis, tetanus and bubonic plague. The most common fatal bacterial diseases are respiratory infections. Antibiotics are used to treat bacterial infections and are also used in farming, making antibiotic resistance a growing problem. Bacteria are important in sewage treatment and the breakdown of oil spills, the production of cheese and yogurt through fermentation, the recovery of gold, palladium, copper and other metals in the mining sector, as well as in biotechnology, and the manufacture of antibiotics and other chemicals. Once regarded as plants constituting the class Schizomycetes ("fission fungi"), bacteria are now classified as prokaryotes. Unlike cells of animals and other eukaryotes, bacterial cells do not contain a nucleus and rarely harbour membrane-bound organelles. Although the term bacteria traditionally included all prokaryotes, the scientific classification changed after the discovery in the 1990s that prokaryotes consist of two very different groups of organisms that evolved from an ancient common ancestor. These evolutionary domains are called Bacteria and Archaea.

ChatGPTRate this definition:0.0 / 0 votes

1. bacteria

   Bacteria are single-celled microorganisms, also known as prokaryotes, existing in various shapes such as rods, spirals, or spheres. They are found everywhere – in the air, soil, water and within other organisms. They play a crucial role in various ecosystem functions such as decomposition and nutrient cycling. Some bacteria are beneficial, aiding in digestion, producing vitamins, and protecting against harmful bacteria, while others cause diseases. They reproduce by binary fission, a rapid process of division that allows their populations to increase quickly.

Webster DictionaryRate this definition:1.0 / 1 vote

1. Bacteria

   see Bacterium

2. Bacteria

   of Bacterium

FreebaseRate this definition:5.0 / 1 vote

1. Bacteria

   Bacteria constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals. Bacteria were among the first life forms to appear on Earth, and are present in most habitats on the planet, growing in soil, water, acidic hot springs, radioactive waste, and deep in the Earth's crust, as well as in organic matter and the live bodies of plants and animals, providing outstanding examples of mutualism in the digestive tracts of humans, termites and cockroaches. There are typically 40 million bacterial cells in a gram of soil and a million bacterial cells in a millilitre of fresh water; in all, there are approximately 5×10^30 bacteria on Earth, forming a biomass that exceeds that of all plants and animals. Bacteria are vital in recycling nutrients, with many steps in nutrient cycles depending on these organisms, such as the fixation of nitrogen from the atmosphere and putrefaction. In the biological communities surrounding hydrothermal vents and cold seeps, bacteria provide the nutrients needed to sustain life by converting dissolved compounds such as hydrogen sulphide and methane. On 17 March 2013, researchers reported data that suggested bacterial life forms thrive in the Mariana Trench, the deepest spot on the Earth. Other researchers reported related studies that microbes thrive inside rocks up to 1900 feet below the sea floor under 8500 feet of ocean off the coast of the northwestern United States. According to one of the researchers,"You can find microbes everywhere — they're extremely adaptable to conditions, and survive wherever they are."

U.S. National Library of MedicineRate this definition:3.7 / 3 votes

1. Bacteria

   One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.

Matched Categories

1. • Microbiology
   • Microorganism

How to pronounce bacteria?

1. Alex

   US English

   David

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   Mark

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   Daniel

   British

   Libby

   British

   Mia

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   Karen

   Australian

   Hayley

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   Priya

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   Neerja

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   Oliver

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   Wendy

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   South African

How to say bacteria in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of bacteria in Chaldean Numerology is: 1

2. Pythagorean Numerology

   The numerical value of bacteria in Pythagorean Numerology is: 5

Examples of bacteria in a Sentence

1. Lund University researcher Tobias Olofsson:

   Well, we've seen in our research that the honey bees actually add great flora of lactic acid bacteria in honey so the mead, when produced, is actually fermented by these lactic acid bacteria together with wild yeasts and the lactic acid bacteria can really kill off all the dangerous pathogens that are even resistant against antibiotics. So our thinking is that the mead, when you consume the mead, these (antibacterial substances in) lactic acid bacteria in the drink can actually be transferred to your blood and help you when you are infected with dangerous bacteria or promote health, preventing infections.

2. Sandria Godwin:

   If there’s bacteria on the surface of a cut of meat, the small tines that pierce the meat could push the bacteria inside, or create more avenues for bacteria to transfer to the inside of the meat.

3. Lisa Dabney:

   The ones that we have on the market now are very, very safe; they are very different from the ones that came out in the ‘80s, [like] the DalkonShield that did have a high risk of pelvic inflammatory disease, one of the main differences was that it had a braded filament--a piece of string that hangs into the vagina-- and bacteria lived in the crevices in the string, which increased the risk of getting pelvic inflammatory disease, which can lead to scarring and blocked fallopian tubes. This caused a scare and caused companies to pull all IUDs [off the shelves] except for the copper IUD. But today, the string is much smoother so the bacteria can’t cling on as easily.

4. Andreas Essig:

   Now copsin kills bacteria by binding to an essential cell wall building block, the cell wall you can consider like the achilles heel of bacteria, so when you disrupt the cell wall synthesis bacteria usually dies rapidly. The binding pattern of copsin on this building block is very unique and therefore copsin is active against bacteria resistant to conventional antibiotics.

5. Holly McClung:

   Interactions between the millions of bacteria living in our gut and what we eat is a very important factor in gut health, but we don't know how MRE foods interact with those bacteria to impact gut health, ultimately, discovering how eating MREs influences gut bacteria and gut health will help our efforts to continually improve the MRE.

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