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n. pl. bac·te·ri·a (-tîr′ē-ə)
1. Any of various prokaryotic microorganisms of the domain Bacteria that may be free-living, saprophytic, commensal, or pathogenic and that vary widely in terms of morphology, oxygen tolerance, nutritional and temperature requirements, and motility. Also called eubacterium.
2. Any of the prokaryotic organisms, such as an archaeon. Not in scientific use.
(Microbiology) the singular of bacteria
bac•te•ri•a(bækˈtɪər i ə)
n.pl., sing. -te•ri•um (-ˈtɪər i əm)
any of numerous groups of microscopic one-celled organisms constituting the phylum Schizomycota, of the kingdom Monera, various species of which are involved in infectious diseases, nitrogen fixation, fermentation, or putrefaction.
[1905–10; < New Latin < Greek baktḗria, pl. of baktḗrion; see bacterium]
Any of a large group of one-celled organisms that lack a cell nucleus, reproduce by fission or by forming spores, and in some cases cause disease. They are found in all living things and in all of the Earth's environments, and usually live off other organisms. Bacteria make up most of the kingdom of prokaryotes.
Usage It is important to remember that bacteria is the plural of bacterium, and that saying a bacteria is incorrect. It is correct to say The soil sample contains millions of bacteria, and Tetanus is caused by a bacterium.
(pl. bacteria) A very small, single-celled, prokaryotic organism.
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|Noun||1.||bacterium - (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|
immune reaction, immune response, immunologic response - a bodily defense reaction that recognizes an invading substance (an antigen: such as a virus or fungus or bacteria or transplanted organ) and produces antibodies specific against that antigen
bioremediation - the act of treating waste or pollutants by the use of microorganisms (as bacteria) that can break down the undesirable substances
probiotic, probiotic bacterium, probiotic flora, probiotic microflora - a beneficial bacterium found in the intestinal tract of healthy mammals; often considered to be a plant
bacteroid - a rodlike bacterium (especially any of the rod-shaped or branched bacteria in the root nodules of nitrogen-fixing plants)
eubacteria, eubacterium, true bacteria - a large group of bacteria having rigid cell walls; motile types have flagella
Calymmatobacterium, genus Calymmatobacterium - a genus of bacterial rods containing only the one species that causes granuloma inguinale
Francisella, genus Francisella - a genus of Gram-negative aerobic bacteria that occur as pathogens and parasite in many animals (including humans)
legionella, Legionella pneumophilia - the motile aerobic rod-shaped Gram-negative bacterium that thrives in central heating and air conditioning systems and can cause Legionnaires' disease
nitrobacterium - any of the bacteria in the soil that take part in the nitrogen cycle; they oxidize ammonium compounds into nitrites or oxidize nitrites into nitrates
penicillin-resistant bacteria - bacteria that are unaffected by penicillin
pus-forming bacteria - bacteria that produce pus
rod - any rod-shaped bacterium
diplococcus - Gram-positive bacteria usually occurring in pairs
superbug - a strain of bacteria that is resistant to all antibiotics
resistance - the degree of unresponsiveness of a disease-causing microorganism to antibiotics or other drugs (as in penicillin-resistant bacteria)
microphage - a neutrophil that ingests small things (as bacteria)
microbiology - the branch of biology that studies microorganisms and their effects on humans
bacterium[bækˈtɪərɪəm] N (bacteria (pl)) → bacteria f
n. bacteria, germen.