Definition of bacterium Bacterium

/bæktɪˈɹiʌm/ - [baktireeum] - bac•te•ri•um

We found 5 definitions of bacterium from 5 different sources.

What does bacterium mean?

WordNet

Noun
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
		bacteria
		micro-organism, microorganism any organism of microscopic size
		microbiology the branch of biology that studies microorganisms and their effects on humans
		acidophil, acidophile an organism that thrives in a relatively acid environment
		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)
		gonococcus, neisseria gonorrhoeae the pus-producing bacterium that causes gonorrhea
		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 pest accidentally imported into Florida from the Middle East then spread to California where it is a very serious pest feeding on almost all vegetable crops and poinsettias

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Wiktionary

bacterium (Noun)
A single celled organism with no nucleus.

Webster DictionaryWebster's Unabridged Dictionary 📘

bacterium (n.)
A microscopic vegetable organism, belonging to the class Algae, usually in the form of a jointed rodlike filament, and found in putrefying organic infusions. Bacteria are destitute of chlorophyll, and are the smallest of microscopic organisms. They are very widely diffused in nature, and multiply with marvelous rapidity, both by fission and by spores. Certain species are active agents in fermentation, while others appear to be the cause of certain infectious diseases. See Bacillus.

Chambers DictionaryChamber's 20th Century Dictionary 📕

bacterium
bak-tē′ri-um, n., Bacteria, bak-tē′ri-a, n.pl. Schizomycetes, extremely small, single-celled, fungoid plants, single or grouped, reproducing rapidly by cross division or by the formation of spores, almost always associated with the decomposition of albuminoid substances, and regarded as the germs or active cause of many diseases.—ns. Bacteriol′ogist; Bacteriol′ogy, the scientific study of bacteria. [Gr. baktērion, dim. of baktron, stick, staff.]