microcephaly

noun

mi·​cro·​ceph·​a·​ly ˌmī-krō-ˈse-fə-lē How to pronounce microcephaly (audio)
: a condition of abnormal smallness of the circumference of the head that is present at birth or develops within the first few years of life and is often associated with developmental delays, impaired cognitive development, poor coordination and balance, deficits in hearing and vision, and seizures

Examples of microcephaly 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.
More than 3,000 babies were born with microcephaly in Brazil during the epidemic. — Harriet Blair Rowan, SFChronicle.com, 22 Sep. 2019 Scientists have already used organoids to make discoveries about schizophrenia, autism spectrum disorders and the microcephaly caused by the Zika virus. — Quanta Magazine, 23 Jan. 2020 Like many children born to mothers infected with Zika while pregnant, Tamara had microcephaly — an underdeveloped brain. — Ari Daniel, NPR, 29 Nov. 2025 And more than half mistakenly thought that the increase in microcephaly cases came about because of childhood vaccinations or a chemical used against the larvae of mosquitoes that transmit Zika to humans. — Gary Stix, Scientific American, 14 Feb. 2020 See All Example Sentences for microcephaly

Word History

Etymology

New Latin microcephalia, from microcephalus microcephalic, from micr- + Greek kephalē head — more at cephalic

First Known Use

1863, in the meaning defined above

Time Traveler
The first known use of microcephaly was in 1863

Rhymes for microcephaly

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Browse Nearby Words

microcephalic
microcephaly
microceratous
See all Nearby Words

Cite this Entry

“Microcephaly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microcephaly. Accessed 8 Jul. 2026.

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Medical Definition

microcephaly

noun
mi·​cro·​ceph·​a·​ly -ˈsef-ə-lē How to pronounce microcephaly (audio)
plural microcephalies
: a condition of abnormal smallness of the circumference of the head that is present at birth or develops within the first few years of life and is often associated with developmental delays, impaired cognitive development, poor coordination and balance, deficits in hearing and vision, and seizures

More from Merriam-Webster on microcephaly

Britannica.com: Encyclopedia article about microcephaly

Last Updated: - Updated example sentences
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