agen·​e·​sis | \ (ˌ)ā-ˈje-nə-səs How to pronounce agenesis (audio) \

Definition of agenesis

: lack or failure of development (as of a body part)

Examples of agenesis in a Sentence

Recent Examples on the Web The 16-year-old, who was born with a rare congenital disorder known as agenesis of the corpus callosum, made a big basket in the game that Legend won 46-32. Joe Rubino, The Denver Post, "Hardwood harmony: Unified Sports brings students, communities together in Douglas County," 21 Feb. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'agenesis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of agenesis

circa 1879, in the meaning defined above

History and Etymology for agenesis

a- entry 2 + genesis, on the model of French agénésie

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Time Traveler for agenesis

Time Traveler

The first known use of agenesis was circa 1879

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Statistics for agenesis

Cite this Entry

“Agenesis.” The Dictionary, Merriam-Webster Inc., Accessed 9 December 2019.

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More Definitions for agenesis


agen·​e·​sis | \ (ˈ)ā-ˈjen-ə-səs How to pronounce agenesis (audio) \
plural ageneses\ -​ˌsēz How to pronounce ageneses (audio) \

Medical Definition of agenesis

: lack or failure of development (as of a body part)

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