[ep-i-dem-ik] 
| 1. | Also, ep⋅i⋅dem⋅i⋅cal. (of a disease) affecting many persons at the same time, and spreading from person to person in a locality where the disease is not permanently prevalent. |
| 2. | extremely prevalent; widespread. |
| 3. | a temporary prevalence of a disease. |
| 4. | a rapid spread or increase in the occurrence of something: an epidemic of riots. |
| ep·i·dem·ic (ěp'ĭ-děm'ĭk) adj.
[French épidémique, from épidémie, an epidemic, from Old French espydymie, from Medieval Latin epidēmia, from Greek epidēmiā, prevalence of an epidemic disease, from epidēmos, prevalent : epi-, epi- + dēmos, people; see dā- in Indo-European roots.] ep'i·dem'i·cal·ly adv. |
A contagious disease that spreads rapidly and widely among the population in an area. Immunization and quarantine are two of the methods used to control an epidemic.
epidemic ep·i·dem·ic (ěp'ĭ-děm'ĭk) or ep·i·dem·i·cal (-ĭ-kəl)
adj.
Spreading rapidly and extensively by infection and affecting many individuals in an area or a population at the same time, as of a disease or illness. n.
An outbreak or unusually high occurrence of a disease or illness in a population or area.
epidemic
an occurrence of disease that is temporarily of high prevalence. An epidemic occurring over a wide geographical area (e.g., worldwide) is called a pandemic. The rise and decline in epidemic prevalence of an infectious disease is a probability phenomenon dependent upon transfer of an effective dose of the infectious agent from an infected individual to a susceptible one. After an epidemic has subsided, the affected host population contains a sufficiently small proportion of susceptible individuals that reintroduction of the infection will not result in a new epidemic. Since the parasite population cannot reproduce itself in such a host population, the host population as a whole is immune to the epidemic disease, a phenomenon termed herd immunity.
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ɪˈdɛm