Infection

n. state of being infected; contamination by germs or disease; something which contaminates or infects, disease

An infection is the detrimental colonization of a host organism by a foreign species. In an infection, the infecting organism seeks to utilize the host's resources to multiply (usually at the expense of the host). The infecting organism, or pathogen, interferes with the normal functioning of the host and can lead to chronic wounds, gangrene, loss of an infected limb, and even death. The host's response to infection is inflammation. Colloquially, a pathogen is usually considered a microscopic organism though the definition is broader, including bacteria, parasites, fungi, viruses, prions, and viroids. A symbiosis between parasite and host, whereby the relationship is beneficial for the former but detrimental to the latter, is characterised as parasitism. The branch of medicine that focuses on infections and pathogens is infectious disease.
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Infection /in·fec·tion/ 1. invasion and multiplication of microorganisms in body tissues, especially that causing local cellular injury due to [more]Infection - Community and Resources

Noun
1. the pathological state resulting from the invasion of the body by pathogenic microorganisms
(hypernym) ill health, unhealthiness, health problem
(hyponym) enterobiasis
(part-meronym) incubation
(derivation) infect, taint
2. (phonetics) the alteration of a speech sound under the influence of a neighboring sound
(hypernym) linguistic process
(classification) phonetics
3. (medicine) the invasion of the body by pathogenic microorganisms and their multiplication which can lead to tissue damage and disease
(hypernym) pathologic process, pathological process
(hyponym) zymosis
(derivation) infect, taint
(classification) medicine, medical specialty
4. an incident in which an infectious disease is transmitted
(synonym) contagion, transmission
(hypernym) incident
(derivation) infect
5. the communication of an attitude or emotional state among a number of people; "a contagion of mirth"; "the infection of his enthusiasm for poetry"
(synonym) contagion
(hypernym) communication
(derivation) infect
6. moral corruption or contamination; "ambitious men are led astray by an infection that is almost unavoidable"
(hypernym) corruptness, corruption
7. (international law) illegality that taints or contaminates a ship or cargo rendering it liable to seizure
(hypernym) illegality
(classification) law, jurisprudence

n. infection, taint