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 Fewer than three of every 1,000 American children with measles will die as a result of severe complications like pneumonia or encephalitis, the swelling of the brain. Apoorva Mandavilli, New York Times, 20 Mar. 2024 Up to 1 in every 20 children will develop pneumonia, and 1 in 1,000 develop a dangerous swelling in the brain called encephalitis that can lead to seizures. Katia Hetter, CNN, 14 Mar. 2024 Measles can cause serious health complications especially in children younger than age 5 including ear infections, diarrhea, pneumonia, encephalitis (swelling of the brain) and even death, according to the CDC. Mary Kekatos, ABC News, 18 Jan. 2024 Prior to his death, MacGowan had been recently hospitalized after being diagnosed with encephalitis,which is an uncommon and potentially life threatening condition that causes the brain to swell, since December 2022 per Sky News. Ilana Kaplan, Peoplemag, 21 Mar. 2024 Complications include ear infections, diarrhea, pneumonia, encephalitis or inflammation of the brain. Haadiza Ogwude, The Enquirer, 15 Mar. 2024 There are also more severe complications that could require hospitalization, which can include pneumonia and encephalitis, or a swelling of the brain. Emily Deletter, USA TODAY, 8 Mar. 2024 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

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 19 Apr. 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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