Definition of EPIDEMIC (original) (raw)
1
: affecting or tending to affect a disproportionately large number of individuals within a population, community, or region at the same time
3
: characterized by very widespread growth or extent : of, relating to, or constituting an epidemic
the practice had reached epidemic proportions
1
: an outbreak of disease that spreads quickly and affects many individuals at the same time : an outbreak of epidemic disease
2
: an outbreak or product of sudden rapid spread, growth, or development
an epidemic of bankruptcies
Usage of Endemic, Epidemic, and Pandemic
This trio of terms describes various degrees of an infectious disease's spread. The process begins with an outbreak—a sudden rise in the presence of a disease. An outbreak that can't be stopped or slowed, and in which the disease is spreading rapidly to many people within a localized community or region (such as a single country), is called an epidemic. The word pandemic refers to an epidemic that has gone international: the disease, once localized in scope, now starts to appear in other countries and even on other continents, typically infecting a large number of people in a short amount of time. A pandemic often has significant economic and social ramifications due to its global impact. If a disease lingers for a long time as an epidemic or a pandemic, it may eventually become endemic to an area. The word endemic describes a disease that persists at a consistent level within a region with fairly predictable rates of infection and spread, making it easier to prevent future outbreaks. Epidemic, pandemic, and endemic all share the Greek root dêmos, meaning "district, country, people."
Synonyms
Examples of epidemic in a Sentence
Adjective
Overuse injuries—particularly in the elbows and shoulders of young pitchers—are indeed becoming epidemic. Orthopedists often blame coaches and parents for failing to monitor how many pitches kids are throwing and for not giving them time to rest their arms. —
Sara Corbett, New York Times Sports Magazine, June 2006 The dream of running off to live the good life in a postcard perfect town in the mountains or by the sea often reaches epidemic proportions near the end of summer. —John Rasmus, National Geographic, September 2004 Saturday Night Fever propelled disco fever to epidemic proportions: By 1978, 40 percent of all the music on Billboard's Hot 100 was disco. —Peter Braunstein, American Heritage, November 1999
the little girl's giggles were epidemic, and soon the entire gathering was laughing Noun
Cosmetic surgery is now so prevalent that it could qualify as a national epidemic. —Toni Bentley, New York Times Book Review, 22 Oct. 2006 "Spim," as people are beginning to call unsolicited instant messages, is the latest installment in the growing epidemic of unwanted electronic ads and a further sign that unscrupulous online marketers will seek to take advantage of all of the Internet's communication tools, not limiting themselves to spam or pop-up ads. —David McGuire, WashingtonPost.com, 13 Nov. 2003 Whatever might have motivated Kennedy to put [Ian] Fleming on his list, from that point, Bond became an international obsession. When the first Bond film appeared in 1962—_Dr. No_—the obsession was a full-blown craze, a cultural epidemic. —Gerald Early, New Letters, 1999
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
But some researchers say the response should not be limited to the epidemic hot spots in big cities. —Byjon Cohen, science.org, 9 Dec. 2024 More than two millennia later, health officials are paying new attention to this old condition for a startling reason: myopia has reached epidemic levels worldwide. —Gary Stix, Scientific American, 1 Oct. 2024
Health programs like those credited with helping end polio and smallpox epidemics and an acclaimed HIV/AIDS program that saved more than 20 million lives in Africa have stopped. —Ellen Knickmeyer, Chicago Tribune, 5 Feb. 2025 The bird flu epidemic began in 2022, and subsequent outbreaks have occurred across the country. —Thomas G. Moukawsher, Newsweek, 5 Feb. 2025 See all Example Sentences for epidemic 
Word History
Etymology
Adjective
borrowed from French épidémique, going back to Middle French, from epidemie "disease affecting a large number of individuals" + -ique -ic entry 1; Middle French epidemie, earlier epydimie, borrowed from Medieval Latin epidēmia, derivative (from feminine singular or neuter plural) of Late Latin epidēmius "widespread, prevalent (of a disease)," borrowed from Greek epidḗmios "within the country, among the people, prevalent (of a disease)," from epi- epi- + -dēmios, adjective derivative of dêmos "district, country, people" — more at demo-
Note: The notion that the word epidemic (adjective or noun) is owed directly to Hippocrates—or is, to put it more circumspectly, part of the Hippocratic Corpus—is somewhat illusory, a product of the words used in English translations. For example, in W. H. S. Jones' translation of De aere aquis et locis (Loeb Classical Library, 1923), the following passage (4.32-34) implies a distinction between "endemic" and "epidemic": "For men these diseases are endemic, besides there are epidemic diseases which may prevail through the change of the seasons." In the Greek text, however, "endemic diseases" are nosḗmata epichōría "illnesses of the country, native illnesses," while "epidemic diseases" translates ti pánkoinon, literally, "something common," i.e., "common or general diseases." Derivatives based on epi- and dêmos can be found in the Hippocratic texts (e.g., "Kaì gàr állōs tò nósēma epídēmon ên," Epidemics 1.14; "Tà mèn epidēmḗsanta nosḗmata taûta," Epidemics 3.3), though epídēmon means simply "common, prevalent," and epidēmḗsanta "having become prevalent." The title Epidḗmia, conventionally translated "Epidemics," for the works in the Hippocratic Corpus dealing with seasonal diseases and case histories, is presumably post-classical.
Noun
noun derivative of epidemic entry 1
First Known Use
Adjective
1603, in the meaning defined at sense 1
Noun
1630, in the meaning defined at sense 2
Time Traveler
The first known use of epidemic was in 1603
Dictionary Entries Near epidemic
Cite this Entry
“Epidemic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/epidemic. Accessed 12 Feb. 2025.
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Last Updated: 3 Jan 2025 - Updated example sentences
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