hydrocephalus

American  

[hahy-druh-sef-uh-luhs] / ˌhaɪ drəˈsɛf ə ləs /

Also hydrocephaly

noun

Pathology.

1. an accumulation of serous fluid within the cranium, especially in infancy, due to obstruction of the movement of cerebrospinal fluid, often causing great enlargement of the head; water on the brain.

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hydrocephalus British  

/ ˌhaɪdrəʊˈsɛfəlɪ, ˌhaɪdrəʊˈsɛfələs, ˌhaɪdrəʊsɛˈfælɪk /

noun

1. Nontechnical name: water on the brain.  accumulation of cerebrospinal fluid within the ventricles of the brain because its normal outlet has been blocked by congenital malformation or disease. In infancy it usually results in great enlargement of the head

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hydrocephalus Scientific  

/ hī′drō-sĕf′ə-ləs /

1. A usually congenital condition in which an abnormal accumulation of cerebrospinal fluid in the cerebral ventricles causes enlargement of the skull and compression of and injury to brain tissue. If hydrocephalus becomes progressive, a shunt is surgically placed to reduce pressure by conducting fluid away from the brain, usually to the peritoneum.

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Other Word Forms

• hydrocephalic adjective

Etymology

Origin of hydrocephalus

1660–70; < Late Latin hydrocephalus ( morbus ) water-headed (sickness), translation of Greek tò hydroképhalon ( páthos ). See hydro- ¹, -cephalous

Example Sentences

Her son, who is referred to as J.M. in the complaint, is nonverbal and autistic and has spina bifida and hydrocephalus.

From Los Angeles Times • Apr. 8, 2026

The news of the home’s reconfiguration came after Joel announced May 23 that he would be calling off his tour to focus on treatment for normal pressure hydrocephalus.

From MarketWatch • Dec. 9, 2025

“And a day does not go by when I don't think about 'What did I do when I was pregnant with him that might've caused the hydrocephalus that has so impacted his life?'”

From Salon • Jan. 31, 2025

He had the operation after an MRI scan in Surrey revealed he had hydrocephalus, a build-up of fluid in the brain.

From BBC • Oct. 10, 2024

Like hydrocephalus, hydrothorax may be idiopathic or symptomatic; and proceed from a local or general cause—the nature of the inflammation being the same in both cases.

From North American Medical and Surgical Journal, Vol. 2, No. 3, July, 1826 by Bache, Franklin