encephalitis

noun

en·​ceph·​a·​li·​tis in-ˌse-fə-ˈlī-təs How to pronounce encephalitis (audio)
plural encephalitides in-ˌse-fə-ˈli-tə-ˌdēz How to pronounce encephalitis (audio)
: inflammation of the brain that is caused especially by infection with a virus (such as herpes simplex or West Nile virus) or less commonly by bacterial or fungal infection or autoimmune reaction

Note: Encephalitis may be asymptomatic or present with mild to severe symptoms (such as fever, headache, confusion, seizures, or loss of consciousness) sometimes progressing to coma or death.

encephalitic adjective

Examples of encephalitis in a Sentence

Recent Examples on the Web About one child in every 1,000 who contract measles can end up with brain swelling, or encephalitis, which can cause convulsions and leave children deaf or with intellectual disabilities, the CDC says. The Enquirer, 15 Mar. 2024 Among reported cases, there were 48,000 hospitalizations, 1,000 cases of encephalitis, or brain swelling, and 500 deaths every year. Discover Magazine, 8 Mar. 2024 Both feature respiratory illness and severe flu-like symptoms, and may progress to encephalitis—inflammation of the brain—along with other neurologic symptoms and death. Erin Prater, Fortune Well, 12 Jan. 2024 Measles can lead to serious complications, especially in children under 2, such as blindness, encephalitis or inflammation of the brain, and severe pneumonia, according to Murray. Amanda Musa, CNN, 23 Jan. 2024 Serious risks include death About a fifth of people who get measles will be hospitalized, while one in 1,000 develop encephalitis, or swelling of the brain, which can result in convulsions, deafness or intellectual disabilities, the city health department said. Eduardo Cuevas, USA TODAY, 9 Jan. 2024 MacGowan — who found major success during the 1980s with the Irish Celtic punk band — is reported to have been in intensive care since his diagnosis with viral encephalitis, per Sky News. Gabrielle Rockson, Peoplemag, 16 Nov. 2023 It would not be known until years later that her mother suffered from brain damage, possibly caused by encephalitis and made worse by alcoholism. Cathleen Decker, Los Angeles Times, 29 Sep. 2023 He was diagnosed with viral encephalitis, a potentially deadly brain inflammation, in December 2022. Conor Murray, Forbes, 30 Nov. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'encephalitis.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1843, in the meaning defined above

Time Traveler
The first known use of encephalitis was in 1843

Dictionary Entries Near encephalitis

Cite this Entry

“Encephalitis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/encephalitis. Accessed 29 Mar. 2024.

Kids Definition

encephalitis

noun
en·​ceph·​a·​li·​tis in-ˌsef-ə-ˈlīt-əs How to pronounce encephalitis (audio)
(ˌ)en-
: inflammation of the brain
also : a disease marked by encephalitis

Medical Definition

encephalitis

noun
en·​ceph·​a·​li·​tis in-ˌsef-ə-ˈlīt-əs How to pronounce encephalitis (audio)
plural encephalitides -ˈlit-ə-ˌdēz How to pronounce encephalitis (audio)
: inflammation of the brain that is caused especially by infection with a virus (such as herpes simplex, varicella zoster, or West Nile virus) or less commonly by bacterial or fungal infection or autoimmune reaction

Note: Encephalitis may be asymptomatic or present with mild to severe symptoms (such as fever, headache, confusion, seizures, or loss of consciousness) sometimes progressing to coma or death.

encephalitic adjective

More from Merriam-Webster on encephalitis

Last Updated: - Updated example sentences
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