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 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

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.


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