hydrocephalus

noun

hy·dro·ceph·a·lus ˌhī-drō-ˈse-fə-ləs

variants or less commonly hydrocephaly

ˌhī-drō-ˈse-fə-lē

: an abnormal increase in the amount of cerebrospinal fluid within the cranial cavity (as from obstructed flow, excess production, or defective absorption) that is accompanied by expansion of the cerebral ventricles and often increased intracranial pressure, skull enlargement, and cognitive decline

Examples of hydrocephalus in a Sentence

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.

Now it’s called hydrocephalus — normal pressure hydrocephalus. — Angelica Stabile, FOXNews.com, 30 Dec. 2025 The musician, 76, explained that he was diagnosed with normal pressure hydrocephalus, and underwent corrective shunt brain surgery last week. — Rachel Desantis, PEOPLE, 25 Nov. 2025 In May, Joel canceled all forthcoming shows, announcing that he’d been diagnosed with a brain disorder known as normal pressure hydrocephalus. — Jami Ganz, New York Daily News, 3 Jan. 2026 The Duke of Sussex was photographed having a sword fight with balloons with 9-year-old Gwen Foster, a girl born with spina bifida and hydrocephalus. — Simon Perry, People.com, 8 Sep. 2025 See All Example Sentences for hydrocephalus

Word History

Etymology

New Latin hydrocephalus, from Late Latin, hydrocephalic, adjective, from Greek hydrokephalos, from hydr- + kephalē head — more at cephalic

First Known Use

1670, in the meaning defined above

Time Traveler

The first known use of hydrocephalus was in 1670

See more words from the same year

Browse Nearby Words

hydrocephalous

hydrocephalus

hydroceramic

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Cite this Entry

Style

“Hydrocephalus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrocephalus. Accessed 7 Jul. 2026.

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Kids Definition

hydrocephalus

noun

hy·dro·ceph·a·lus ˌhī-drō-ˈsef-ə-ləs

variants also hydrocephaly

-ˈsef-ə-lē

: an abnormal condition in which an increased amount of cerebrospinal fluid causes an increase in the size of the ventricles of the brain and the size of the skull and the wasting away of the brain

Medical Definition

hydrocephalus

noun

hy·dro·ceph·a·lus -ˈsef-ə-ləs, British also -ˈkef-

plural hydrocephali -ˌlī

hydrocephalus

noun

Examples of hydrocephalus in a Sentence

Word History

Browse Nearby Words

Cite this Entry

Kids Definition

Medical Definition

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