from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun Formation of a placenta in the uterus.
- noun The type or structure of a placenta.
- noun Botany Arrangement of placentas within the ovary.
from The Century Dictionary.
- noun In zoology: The attachment of the embryo or fetus to the uterus by means of a placenta; uterogestation.
- noun The mode in which this attachment is effected; the manner of the disposition or construction of the placenta: as, deciduate or discoidal Placentation.
- noun In botany, the disposition or arrangement of the placentas.
from the GNU version of the Collaborative International Dictionary of English.
- noun (Anat.) The mode of formation of the placenta in different animals.
- noun (Bot.) The mode in which the placenta is arranged or composed
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun biology the local
fusionof the embryonicstage of an animalto its parentfor physiological exchangeto promote the growthand developmentof the young; involves a placentain non-egglaying mammals
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- noun the formation of the placenta in the uterus
- noun arrangement of the ovules in the placenta and of the placentas in the ovary
Sorry, no etymologies found.
Lucy did have one umbilical artery, and also at deliver, there was a little bit of abnormal placentation of the cord of the placenta.
Nurse Callan taken aback in the hallway cannot stay them nor smiling surgeon coming downstairs with news of placentation ended, a full pound if a milligramme.
The late Professor E. Forbes describes  an instance of true foliar and true axile placentation in the same flower in _Vinca minor_.
We find the bottom of the tube is occupied by two cells, partially filled with ovula, which are attached both to the axis and to the base, as well as to the lower part of the outer paries of each cell; so far, it does not depart from the order, for in Aplexus the placentation is tolerably similar.
It will be remembered, also, how, in certain natural orders, under ordinary circumstances, considerable diversity in placentation exists, according as the margins of the carpels are merely valvate or are infolded so as to reach the centre.
Sutural, parietal, axile, free-central placentation, and, if there be more forms, all may be met with even in the same ovary (see pp. 96, 508).
The true place of Moringa seems to be near Xanthophyllum with which genus it has some remarkable points of resemblance, witness the papilionaceous corolla; unilocular stamina, their situation, ovary, placentation, and lastly glandulation.
To Santalaceae they approach in processes, valvate corolla, and placentation, also to Loranthaceae.
First, we have in the bottom from which the mere structure of an ovary is deduced, the normal dicarpellary structure, and there is in addition a tendency in excess toward a parietal placentation.
_Rhododendron_ I have observed a similar condition of the ovules, which, moreover, in the primary flowers, were attached to the walls of the carpels -- parietal placentation.