contagion

noun

con·​ta·​gion kən-ˈtā-jən How to pronounce contagion (audio)
1
a
: a contagious disease
b
: the transmission of a disease by direct or indirect contact
c
: a disease-producing agent (such as a virus)
2
a
: poison
b
: contagious influence, quality, or nature
c
: corrupting influence or contact
3
a
: rapid communication of an influence (such as a doctrine or emotional state)
b
: an influence that spreads rapidly

Examples of contagion in a Sentence

a disease that spreads by contagion People have been warned to keep out of the area to avoid contagion.
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.
Complex contagion may have taken hold, in a malicious way, and begun spreading falsehood throughout the network at a rapid pace. Shaon Lahiri, The Conversation, 7 July 2025 Social media and hybrid workplaces have made our environments even more porous such that contagion spreads faster—emotionally and professionally. Ellen Choi, Forbes.com, 30 June 2025 Instead of the Rage Virus becoming an international contagion, it's revealed the disease's spread was ultimately contained to the UK, where survivors were left to figure things out on their own as the rest of the world moved on. Megan McCluskey, Time, 20 June 2025 The episode opens on a very mysterious note introducing a new way in which the Cordyceps contagion manages to transmit itself. Matt Minton, Variety, 12 May 2025 See All Example Sentences for contagion

Word History

Etymology

Middle English contagioun, borrowed from Anglo-French & Latin; Anglo-French contagiun, borrowed from Latin contāgiōn, contāgiō "contact, contact resulting in disease, infection, pollution," from contag-, variant stem of contingere "to be in contact with, arrive at, affect, fall to one's lot" + -iōn-, -iō, suffix of action nouns formed from compound verbs — more at contingent entry 1

Note: The vowel length in contāgiō is unexpected and difficult to explain; a similarly lengthened vowel is found in other deverbal derivatives with -ag- as a second member (compāgēs "bond, joint," from pangere, ambāgēs "circuitous path," from agere; see agent, pact).

First Known Use

14th century, in the meaning defined at sense 1a

Time Traveler
The first known use of contagion was in the 14th century

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Cite this Entry

“Contagion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/contagion. Accessed 13 Jul. 2025.

Kids Definition

contagion

noun
con·​ta·​gion kən-ˈtā-jən How to pronounce contagion (audio)
1
: the passing of a disease from one individual to another by direct or indirect contact
2
: a contagious disease or something (as a virus) that causes a contagious disease

Medical Definition

contagion

noun
con·​ta·​gion kən-ˈtā-jən How to pronounce contagion (audio)
1
: the transmission of a disease by direct or indirect contact
2
3
: a disease-producing agent (as a virus)

More from Merriam-Webster on contagion

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