placentation

[ plas-uhn-tey-shuhn ]

noun
  1. Anatomy, Zoology.

    • the formation of a placenta.

    • the manner of placement or construction of a placenta.

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

Origin of placentation

1
From French, dating back to 1750–60; see origin at placenta, -ation

Words Nearby placentation

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use placentation in a sentence

  • To Santalaceæ they approach in processes, valvate corolla, and placentation, also to Loranthaceæ.

  • 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
  1. botany the way in which ovules are attached in the ovary

  2. zoology

    • the way in which the placenta is attached in the uterus

    • the process of formation of the placenta

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