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 There are many forms of encephalitis, but this is the most common form of encephalitis in children, Nathan's doctors tell PEOPLE. Wendy Grossman Kantor, Peoplemag, 21 Mar. 2023 According to the Mayo Clinic, encephalitis is inflammation of the brain that can be caused by such things as a viral infection, bacterial infection, autoimmune inflammation and insect bites. Gabrielle Rockson, Peoplemag, 16 Nov. 2023 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. Byerin Prater, Fortune Well, 10 Nov. 2023 For example, severe flu can lead to myocarditis (inflammation of the heart), encephalitis (inflammation of the brain), and multiorgan failure, particularly of the kidneys and lungs. Nick Blackmer, Verywell Health, 9 Nov. 2023 That illness led to her contracting Ramsay Hunt syndrome as well as encephalitis, an inflammation of the brain that can cause lasting memory and language problems, as well as bouts of confusion. Ella Sherman, The New Republic, 2 Oct. 2023 Severe cases start with the sudden onset of a headache, high fever, chills and vomiting before progressing to disorientation, seizures, encephalitis and coma. Leada Gore | Lgore@al.com, al, 24 Aug. 2023 Symptoms include frequent and severe seizures, inflammation of the brain (otherwise known as encephalitis), mental deterioration and the progressive loss of neurological functions such as motor skills, speech and mobility on one side of the body, per NINDS. Alexis Jones, Peoplemag, 9 Oct. 2023 About one in 150 people infected with West Nile virus will develop severe disease leading to encephalitis, which is inflammation of the brain, or meningitis, which is inflammation of the membranes that surround the brain and spinal cord. Mary Kekatos, ABC News, 3 Oct. 2023 See More

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 8 Dec. 2023.

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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