Definitions of micro-organism

n any organism of microscopic size

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(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
(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
bug, germ, microbe
a minute life form (especially a disease-causing bacterium); the term is not in technical use
any disease-producing agent (especially a virus or bacterium or other microorganism)
any of the unicellular protists
protist, protistan
free-living or colonial organisms with diverse nutritional and reproductive modes
microscopic plants; bacteria are often considered to be microflora
arborvirus, arbovirus
a large heterogeneous group of RNA viruses divisible into groups on the basis of the virions; they have been recovered from arthropods, bats, and rodents; most are borne by arthropods; they are linked by the epidemiologic concept of transmission between vertebrate hosts by arthropod vectors (mosquitoes, ticks, sandflies, midges, etc.) that feed on blood; they can cause mild fevers, hepatitis, hemorrhagic fever, and encephalitis
bacteriophage, phage
a virus that is parasitic (reproduces itself) in bacteria
plant virus
a plant pathogen that is a virus consisting of a single strand of RNA
animal virus
an animal pathogen that is a virus
slow virus
a virus that remains dormant in the body for a long time before symptoms appear
archaebacteria, archaebacterium, archaeobacteria, archeobacteria
considered ancient life forms that evolved separately from bacteria and blue-green algae
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
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)
Neisseria gonorrhoeae, gonococcus
the pus-producing bacterium that causes gonorrhea
tumor virus
a cell-free filtrate held to be a virus responsible for a specific neoplasm
(genetics) a virus or other agent that is used to deliver DNA to a cell
Legionella pneumophilia, legionella
the motile aerobic rod-shaped Gram-negative bacterium that thrives in central heating and air conditioning systems and can cause Legionnaires' disease
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
any rod-shaped bacterium
Gram-positive bacteria usually occurring in pairs
protozoan, protozoon
any of diverse minute acellular or unicellular organisms usually nonphotosynthetic
alga, algae
primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves
a strain of bacteria that is resistant to all antibiotics
Type of:
being, organism
a living thing that has (or can develop) the ability to act or function independently

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