placentation en · NOUN
Etymology
Etymology tree English placenta Proto-Indo-European *-tis Proto-Indo-European *-Hō Proto-Indo-European *-tiHō Proto-Italic *-tiō Latin -tiō Latin -ātiōlbor. Old French -ationbor. Middle English -acioun English -ation English placentation From placenta + -ation.
Meanings
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(countable, uncountable) The local fusion of the embryonic stage of an animal to its parent for physiological exchange to promote the growth and development of the young; involves a placenta in non-egglaying mammals.
Specialized hemophagous regions are a striking characteristic of some of these placentas yet absent in hyraxes, elephant shrews, and golden moles. It is possible that the common ancestor of the Afrotheria had an endotheliochorial placenta.
2004, “Placentation in species of phylogenetic importance: the Afrotheria”, in Animal Reproduction Science:
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(countable, uncountable) The manner in which the seeds are attached to the placenta within the ovary locules.
Parietal placentation occurs in the Brassicaceae family.
Forms
| Spelling | Features | Labels | Source |
|---|---|---|---|
| placentations | Number=Plur | lexicographic |