pla·​cen·​ta·​tion | \ˌpla-sᵊn-ˈtā-shən, plə-ˌsen-\

Definition of placentation 

1 : the arrangement of placentas and ovules in a plant ovary

2a : the development of the placenta and attachment of the fetus to the uterus during pregnancy

b : the morphological type of a placenta

Examples of placentation in a Sentence

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Another possible cause for higher hormone levels leading to excessive nausea is something called abnormal placentation, where the placenta overgrows, says Liu, adding that this happens only occasionally. Miriam Falco And Alanne Orjoux, CNN, "What is hyperemesis gravidarum?," 4 Sep. 2017

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

First Known Use of placentation

1760, in the meaning defined at sense 1

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The first known use of placentation was in 1760

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pla·​cen·​ta·​tion | \ˌplas-ᵊn-ˈtā-shən, plə-ˌsen- \

Medical Definition of placentation 

1 : the development of the placenta and attachment of the fetus to the uterus during pregnancy

2 : the morphological type of a placenta

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to enclose within walls

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