contagious

play

adjective con·ta·gious \kən-ˈtā-jəs\

Definition of contagious

1 : transmissible by direct or indirect contact with an infected person contagious diseases
2 : bearing contagion contagious people
3 : used for contagious diseases a contagious ward
4 : exciting similar emotions or conduct in others contagious enthusiasm contagious laughter

contagiously

adverb

contagiousness

noun

See contagious defined for English-language learners

See contagious defined for kids

Examples of contagious in a Sentence

It's a highly contagious virus.
I have a cold and I'm still contagious.
I'm sick, but the doctor says I'm not contagious.

Recent Examples of contagious from the Web

Valeria Merino/Courier-Journal/USA Today Network At least four dogs at Louisville Metro Animal Services have had positive test results for a highly contagious strain of dog flu, the department announced Friday.

— darcy costello, The Courier-Journal, "Highly contagious dog flu outbreak reaches Louisville Metro Animal Services," 14 July 2017
Delusion is contagious, competent criminals are hard to catch and there’s no empirical reason to believe Gulati, Garber or the rest of the current American soccer establishment was cognizant or complicit.

— brian straus, SI.com, "Chuck Blazer's trail of corruption, crime leaves U.S. colleagues facing his complex legacy," 13 July 2017
The Tasmanian devil was nearly wiped out 20 years ago when a contagious tumor began disfiguring its face and killing animals by the hundreds.

— elizabeth pennisi, Science | AAAS, "Rogue chromosome may be behind new contagious cancer striking Tasmanian devils," 10 July 2017
Doctors did not understand what was happening or whether the cancer was contagious.

— erin blakemore, Smithsonian, "This Was the First Major News Article on HIV/AIDS," 3 July 2017
Smallpox and other contagious diseases spread over the canal, too.

— lorraine boissoneault, Smithsonian, "Thank the Erie Canal For Spreading People, Ideas and Germs Across America," 3 July 2017
With brass blasting and drums beating, the music was contagious.

— dorothy andries, chicagotribune.com, "Pink Martini headlines lively CSO Corporate Night party," 30 June 2017
Every page brims with the contagious mania of tech-bro self-improvement.

— stella bugbee, The Cut, "I Hate This Book About Lifehacks, But I Can’t Stop Reading It," 30 June 2017
Bogdan Botezatu, an analyst with Bitdefender, compared the new program to a contagious disease.

— Washington Post, "New highly virulent strain of ransomware cripples networks," 28 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'contagious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of contagious

see contagion

NEW! Time Traveler

First Known Use: 14th century

See Words from the same year

Other Medicine Terms

analgesia, angina, diabetes, hepatitis, homeopathy, logorrhea, palliate, pandemic

CONTAGIOUS Defined for English Language Learners

contagious

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adjective

Definition of contagious for English Language Learners

: able to be passed from one person or animal to another by touching
: having a sickness that can be passed to someone else by touching
: capable of being easily spread to others : causing other people to feel or act a similar way

CONTAGIOUS Defined for Kids

contagious

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adjective con·ta·gious \kən-ˈtā-jəs\

Definition of contagious for Students

1 : able to be passed from one individual to another through contact a contagious disease
2 : having a sickness that can be passed to someone else
3 : causing other people to feel or act a similar way a contagious laugh

Medical Dictionary

contagious

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adjective con·ta·gious \-jəs\

Medical Definition of contagious

1: communicable by contact tuberculosis in the contagious stage—compare infectious 2
2: bearing contagion many persons…are contagious long before they are aware of the presence of their disease—Journal of the American Medical Association
3: used for contagious diseases a contagious ward