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.
The epidemiology – and now the outbreak at Lackland – tell a different story. — Katrine L. Wallace, The Conversation, 24 June 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 Ben Lopman is professor of epidemiology and global health at Emory University’s Rollins School of Public Health. — Ben Lopman, STAT, 2 July 2026 While initially focused on pharmaceutical drug discovery, demonstrated by rapidly screening compounds for rare diseases, its general architecture promises vast applications in field sciences like epidemiology. — John Drake, Forbes.com, 30 June 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 7 Jul. 2026.

Copy Citation

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
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Popular in Grammar & Usage

See More

Is that lie 'bald-faced' or 'bold-faced'?

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?

Commonly Misspelled Words

How to Use Em Dashes (—), En Dashes (–) , and Hyphens (-)
See More

Popular in Wordplay

See More

14 Phobias You Probably Haven't Heard Of

The Longest Long Words List

One-Word Oxymorons: Bittersweet, Spendthrift, and More

Ten Words Ending with a Silent ‘T’

12 Lovely and Unusual Words for the Natural World
See More

Popular

See More

Is that lie 'bald-faced' or 'bold-faced'?

14 Phobias You Probably Haven't Heard Of

The Longest Long Words List
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
hangman letters and game
Hangman Lightning Round Figure out which word fits in the blanks.
See All