placenta

noun pla·cen·ta \ plə-ˈsen-tə \
Updated on: 20 Nov 2017

Definition of placenta

plural placentas or placentae play \plə-ˈsen-(ˌ)tē\
1 : the vascular organ in mammals except monotremes and marsupials that unites the fetus to the maternal uterus and mediates its metabolic exchanges through a more or less intimate association of uterine mucosal with chorionic and usually allantoic tissues; also : an analogous organ in another animal
2 : a sporangium-bearing surface; especially : the part of the carpel bearing ovules

Recent Examples of placenta from the Web

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Origin and Etymology of placenta

New Latin, from Latin, flat cake, from Greek plakoenta, accusative of plakoeis, from plak-, plax flat surface — more at fluke


PLACENTA Defined for English Language Learners

placenta

noun

Definition of placenta for English Language Learners

  • medical : the organ in mammals that forms inside the mother's uterus, nourishes the unborn baby, and is pushed out of the mother after the birth of the baby


PLACENTA Defined for Kids

placenta

noun pla·cen·ta \ plə-ˈsen-tə \

Definition of placenta for Students

: the organ in most mammals by which the fetus is joined to the uterus of the mother and is nourished

Medical Dictionary

placenta

noun pla·cen·ta \ plə-ˈsent-ə \

medical Definition of placenta

plural placentas or placentae play \-ˈsent-(ˌ)ē\
: the vascular organ in mammals except monotremes and marsupials that unites the fetus to the maternal uterus and mediates its metabolic exchanges through a more or less intimate association of uterine mucosal with chorionic and usually allantoic tissues permitting exchange of material by diffusion between the maternal and fetal vascular systems but without direct contact between maternal and fetal blood and typically involving the interlocking of fingerlike vascular chorionic villi with corresponding modified areas of the uterine mucosa — see abruptio placentae

Illustration of placenta



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