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
ˌe-pə-ˌdē-mē-ə-ˈlä-ji-kəl How to pronounce epidemiology (audio) -ˌde-mē- How to pronounce epidemiology (audio)
adjective
or less commonly epidemiologic
ˌe-pə-ˌdē-mē-ə-ˈlä-jik How to pronounce epidemiology (audio)
-ˌde-mē-
epidemiologically
ˌe-pə-ˌdē-mē-ə-ˈlä-ji-k(ə-)lē How to pronounce epidemiology (audio)
-ˌde-mē-
adverb
epidemiologist
ˌe-pə-ˌdē-mē-ˈä-lə-jist How to pronounce epidemiology (audio) -ˌde-mē- How to pronounce epidemiology (audio)
noun

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.
That was one of my biggest takeaways — and bummers — from my conversation with Chris Barker, an epidemiology professor at UC Davis who has studied mosquitoes for almost 30 years, including at his lab. — Jaclyn Cosgrove, Los Angeles Times, 13 Aug. 2026 Mbala is a Congolese virologist and the head of epidemiology and global health at the National Institute of Biomedical Research in the Democratic Republic of the Congo. — Krutika Kuppalli, STAT, 10 Aug. 2026 After earning his medical degree from Columbia University and teaching there as an epidemiology professor, el Sayed became the youngest-ever health director of the Detroit Health Department at the age of 30, serving from 2015 to 2017. — Gabrielle M. Etzel, The Washington Examiner, 9 Aug. 2026 Before the system exists there is nothing to fit to, so the epidemic’s starting point is set by an assumption placed near the beginning of the data window rather than estimated from the epidemiology. — John Drake, Forbes.com, 4 Aug. 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

Rhymes for epidemiology

See All Rhymes for epidemiology

Browse Nearby Words

epidemic curve
epidemiology
epidemy
See all Nearby Words

Cite this Entry

“Epidemiology.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/epidemiology. Accessed 17 Aug. 2026.

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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
-mē-ə-ˈläj-i-kəl How to pronounce epidemiology (audio)
adjective
also epidemiologic
-ˈläj-ik How to pronounce epidemiology (audio)

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
-ˌdē-mē-ə-ˈläj-i-kəl How to pronounce epidemiology (audio) -ˌdem-ē- How to pronounce epidemiology (audio)
adjective
also epidemiologic
-ik How to pronounce epidemiology (audio)
epidemiologically
-i-k(ə-)lē How to pronounce epidemiology (audio)
adverb

More from Merriam-Webster on epidemiology

Britannica.com: Encyclopedia article about epidemiology

Last Updated: - Updated example sentences
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