Epidemical

[ep-i-dem-ik] /ˌɛp ɪˈdɛm ɪk/

adjective
1.
Also, epidemical. (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.
noun
3.
a temporary prevalence of a disease.
4.
a rapid spread or increase in the occurrence of something:
an epidemic of riots.
/ˌɛpɪˈdɛmɪk/
adjective
1.
(esp of a disease) attacking or affecting many persons simultaneously in a community or area
noun
2.
a widespread occurrence of a disease: an influenza epidemic
3.
a rapid development, spread, or growth of something, esp something unpleasant: an epidemic of strikes
adj.

c.1600, from French épidémique, from épidemié “an epidemic disease,” from Medieval Latin epidemia, from Greek epidemia “prevalence of an epidemic disease” (especially the plague), from epi “among, upon” (see epi-) + demos “people, district” (see demotic).
n.

1757, from epidemic (adj.); earlier epideme (see epidemy). An Old English noun for this (persisting in Middle English) was man-cwealm.

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
(ěp’ĭ-děm’ĭk)
An outbreak of a disease or illness that spreads rapidly among individuals in an area or population at the same time. See also endemic, pandemic.

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.