epidemiology

noun

ep·​i·​de·​mi·​ol·​o·​gy ˌe-pə-ˌdē-mē-ˈä-lə-jē How to pronounce epidemiology (audio)
-ˌde-mē-
1
: a branch of medical science that deals with the incidence, distribution, and control of disease in a population
2
: the sum of the factors controlling the presence or absence of a disease or pathogen
epidemiological adjective
or less commonly epidemiologic
epidemiologically adverb

Examples of epidemiology in a Sentence

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.
Sykes is a professor of medicine and epidemiology at University of California Davis Weill School of Veterinary Medicine. The Washington Post, San Diego Union-Tribune, 28 Feb. 2026 In an interview, Alex Kral, a researcher with RTI International focused on drug use epidemiology, theorized that use trends could be partly linked to climate. Lev Facher, STAT, 12 Feb. 2026 Sunil Parikh, a professor of epidemiology and infectious diseases at the Yale School of Public Health, has studied ivermectin for the treatment of malaria. Cindy Krischer Goodman, Sun Sentinel, 6 Feb. 2026 Each country makes choices based on their healthcare system, infectious disease epidemiology, and ability to manage disease risk. Washington Post, 7 Jan. 2026 See All Example Sentences for epidemiology

Word History

Etymology

borrowed from French, Spanish, or New Latin; French épidémiologie, borrowed from Spanish epidemiología, borrowed from New Latin epidēmiologia, from Medieval Latin epidēmia "disease affecting a large number of individuals, epidemic" + New Latin -o- -o- + -logia -logy — more at epidemic entry 1

Note: New Latin epidēmiologia was used in the title of a treatise by the Calabrian physician Quinto Tiberio Angelerio (1532-1617), Epidemiologia, sive Tractatus de peste (Madrid, 1598), a second edition of his earlier work Ectypa pestilentis status Algheriae Sardiniae (Cagliari, 1588), detailing methods to cope with a plague outbreak in Alghero, Sardinia, in 1582-83. The Latin word was revived by the Spanish physician Joaquín de Villalba (1752-1807) in his Epidemiología española (Madrid, 1802), a history of epidemics in Spain that was widely disseminated in Europe.

First Known Use

1850, in the meaning defined at sense 1

Time Traveler
The first known use of epidemiology was in 1850

Browse Nearby Words

Cite this Entry

“Epidemiology.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/epidemiology. Accessed 9 Mar. 2026.

Kids Definition

epidemiology

noun
ep·​i·​de·​mi·​ol·​o·​gy ˌep-ə-ˌdē-mē-ˈäl-ə-jē How to pronounce epidemiology (audio)
1
: a branch of medical science that deals with the occurrence, distribution, and control of disease in a population
2
: the sum of the factors controlling the presence or absence of a particular disease
epidemiological adjective
also epidemiologic

Medical Definition

epidemiology

noun
ep·​i·​de·​mi·​ol·​o·​gy -jē How to pronounce epidemiology (audio)
plural epidemiologies
1
: a branch of medical science that deals with the incidence, distribution, and control of disease in a population
2
: the sum of the factors controlling the presence or absence of a disease or pathogen
epidemiological adjective
also epidemiologic
epidemiologically adverb

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