What does anencephaly mean?
Anencephaly is a congenital neural tube disorder in which the cranial vault and major parts of the brain fail to develop normally. It is commonly associated with incomplete closure of the anterior neuropore early in embryonic development, although other developmental processes may also contribute. The condition is medically serious and is distinct from individual differences in brain development or from health problems that appear later in life. In writing, anencephaly is normally used as a formal clinical noun: clinicians and public-health professionals discuss cases, screening, and outcomes, while families and advocacy organizations use the term when describing pregnancies involving fetal anencephaly and people affected by the condition. It is also a useful word because it identifies a specific and severe form of neural tube defect rather than describing a complex congenital condition as merely a vague absence of a brain. The corresponding adjective is anencephalic.
nounA congenital neural tube defect in which the cranial vault and major portions of the brain are absent, most commonly associated with failure of the anterior neuropore to close during early embryonic development.
- A congenital neural tube defect characterized by the absence of the cranial vault and major portions of the brain.
"Prenatal screening identified anencephaly during the second trimester."
"The ultrasound revealed findings consistent with anencephaly."
"Public-health programs provide information about anencephaly and other neural tube defects."
Usually treated as an uncountable medical noun; a distinct plural form is not standard.
"Research is continuing on the causes and prevention of anencephaly."
Anencephaly is one of the most severe neural tube disorders: the cranial vault and most of the brain fail to develop.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does anencephaly come from?
The word combines the Greek prefix an-, meaning “without,” with enkephalos, meaning “brain,” which is itself related to en-, “in,” and kephalē, “head.” The compound was established in English medical usage by the 19th century. Its relatives, including encephalitis, encephalopathy, and encephalography, likewise involve the brain or the study of it.
Related word forms
How anencephaly is actually used
This is a formal, specialized medical term, used especially in clinical, prenatal, public-health, and educational contexts. It refers to the congenital condition rather than to an acquired injury or a general absence of cognitive function.