placentation

[ plas-uhn-tey-shuhn ]

/ ˌplæs ənˈteɪ ʃən /

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noun

Anatomy, Zoology.

the formation of a placenta.
the manner of placement or construction of a placenta.

Botany. the disposition or arrangement of a placenta or placentas.

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Origin of placentation

From French, dating back to 1750–60; see origin at placenta, -ation

Words nearby placentation

placement test, placename, placenta, placental, placentate, placentation, Placentia, Placentia Bay, place of arms, place of articulation, place of safety order

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use placentation in a sentence

To Santalaceæ they approach in processes, valvate corolla, and placentation, also to Loranthaceæ.
Journals of Travels in Assam, Burma, Bhootan, Afghanistan and The|William Griffith
In the flowers of Saponaria officinalis Dr. Masters has observed instances of both marginal and free central placentation.
On the Origin of Species|Charles Darwin
The disjunction or dialysis of the carpels, for instance, frequently renders axile placentation marginal.
Vegetable Teratology|Maxwell T. Masters
In double flowers of Primulaceæ similar alterations in the placentation may often be observed.
Vegetable Teratology|Maxwell T. Masters

The same excellent observer has recorded the occurrence of free central placentation in malformed flowers of Trifolium repens.
Vegetable Teratology|Maxwell T. Masters

British Dictionary definitions for placentation

placentation

/ (ˌplæsɛnˈteɪʃən) /

noun

botany the way in which ovules are attached in the ovary

zoology

the way in which the placenta is attached in the uterus
the process of formation of the placenta

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012