microorganism

mi·cro·or·gan·ism  (mkr-ôrg-nzm)

n.

An organism of microscopic or submicroscopic size, especially a bacterium or protozoan.

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microorganism

Noun

any organism of microscopic size, such as a virus or bacterium

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microorganism  (mkr-ôrg-nzm)

An organism that can be seen only with the aid of a microscope and that typically consists of only a single cell. Microorganisms include bacteria, protozoans, and certain algae and fungi. See Note at germ.

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microorganism

any one of a large variety of microscopic or ultramicroscopic organisms, as bacteria, viruses, etc.

See also: Organisms

Thesaurus

Noun

1.

microorganism - any organism of microscopic size     micro-organism organism, being - a living thing that has (or can develop) the ability to act or function independently animal, animate being, beast, creature, fauna, brute - a living organism characterized by voluntary movement plant life, flora, plant - (botany) a living organism lacking the power of locomotion monad - (biology) a single-celled microorganism (especially a flagellate protozoan) intestinal flora - harmless microorganisms (as Escherichia coli) that inhabit the intestinal tract and are essential for its normal functioning virus - (virology) ultramicroscopic infectious agent that replicates itself only within cells of living hosts; many are pathogenic; a piece of nucleic acid (DNA or RNA) wrapped in a thin coat of protein moneran, moneron - organisms that typically reproduce by asexual budding or fission and whose nutritional mode is absorption or photosynthesis or chemosynthesis bacteria, 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 microbe, germ, bug - a minute life form (especially a disease-causing bacterium); the term is not in technical use pathogen - any disease-producing agent (especially a virus or bacterium or other microorganism) protoctist - any of the unicellular protists protist, protistan - free-living or colonial organisms with diverse nutritional and reproductive modes pilus - hairlike structure especially on the surface of a cell or microorganism virulence, virulency - extreme harmfulness (as the capacity of a microorganism to cause disease); "the virulence of the plague" transmitter, vector - any agent (person or animal or microorganism) that carries and transmits a disease; "mosquitos are vectors of malaria and yellow fever"; "fleas are vectors of the plague"; "aphids are transmitters of plant diseases"; "when medical scientists talk about vectors they are usually talking about insects" microflora - microscopic plants; bacteria are often considered to be microflora bacteremia, bacteriaemia, bacteriemia - transient presence of bacteria (or other microorganisms) in the blood