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.
The federal cuts make preparing for the World Cup a daunting task for federal, state and local public health agencies, said Jennifer Nuzzo, a professor of epidemiology and director of the pandemic center at Brown University School of Public Health. Swapna Venugopal Ramaswamy, USA Today, 6 June 2026 Why reading is good for your brain Bone, a senior research fellow in statistics and epidemiology at University College London, said these events might not necessarily mean more adults are leisure reading, which can include physical and e-books, magazines and newspapers. Sneha Dhandapani, CNN Money, 6 June 2026 Fentanyl arrived in the Mountain West later than in the rest of the country, so the region might simply not be as far along the curve of reducing deaths, said Thomas Stopka, a professor of epidemiology at Tufts University School of Medicine. Meg Wingerter, Denver Post, 20 May 2026 Juan Petrina, director of epidemiology for the Tierra del Fuego province, shows a laptop screen after a news conference in Ushuaia on Friday. Marlene Lenthang, NBC news, 10 May 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 Jun. 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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