Definitions for placentapləˈsɛn tə
Random House Webster's College Dictionary
pla•cen•ta*pləˈsɛn tə(n.)(pl.)-tas, -tae
the organ in most mammals, formed in the lining of the uterus by the union of the uterine mucous membrane with the membranes of the fetus, that provides for the nourishment of the fetus and the elimination of its waste products.
Category: Anatomy, Zoology
the part of the ovary of flowering plants that bears the ovules. (in ferns and related plants) the tissue giving rise to sporangia.
Origin of placenta:
1670–80; < NL: something having a flat, circular form, L: a cake < Gk plakóenta, acc. of plakóeis flat cake, der. of pláx (gen. plakós) flat
that part of the ovary of a flowering plant where the ovules form
the vascular structure in the uterus of most mammals providing oxygen and nutrients for and transferring wastes from the developing fetus
A vascular organ in mammals, except monotremes and marsupials, present only in the female during gestation. It supplies food and oxygen from the mother to the foetus, and passes back waste. It is implanted in the wall of the uterus and links to the foetus through the umbilical cord. It is expelled after birth.
In flowering plants, the part of the ovary where ovules develop; in non-flowering plants where the spores develop.
the vascular appendage which connects the fetus with the parent, and is cast off in parturition with the afterbirth
the part of a pistil or fruit to which the ovules or seeds are attached
U.S. National Library of Medicine
A highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (CHORIONIC VILLI) derived from TROPHOBLASTS and a maternal portion (DECIDUA) derived from the uterine ENDOMETRIUM. The placenta produces an array of steroid, protein and peptide hormones (PLACENTAL HORMONES).