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 Dave was born with sacral agenesis, a congenital condition in which the lowest portion of the spine that forms the joint with the hips fails to develop. Richard Sandomir, New York Times, "David Toole, Disabled Dancer With Grace in His Hands, Dies at 56," 10 Nov. 2020 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

Last Updated

28 Nov 2020

Cite this Entry

“Agenesis.” Dictionary, Merriam-Webster, Accessed 24 Jan. 2021.

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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 agenesis (audio) \

Medical Definition of agenesis

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

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