congenital absence of part or all of the brain.
Also an·en·ce·pha·lia [an-en-suh-feyl-yuh, an-en-] /ˌæn ɛn səˈfeɪl yə, ænˌɛn-/.
Origin of anencephaly
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for anencephalous
Historical Examples of anencephalous
It has been observed likewise in anencephalous monsters (Brissot, idem).
In a former article I alluded to encephalous and anencephalous cases, where there were either no heads or heads without brains.Curiosities of Medical Experience
J. G. (John Gideon) Millingen
Congenital absence of most of the brain and spinal cord.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.