noun, plural pla·cen·tas, pla·cen·tae [pluh-sen-tee] /pləˈsɛn ti/.
- the part of the ovary of flowering plants that bears the ovules.
- (in ferns and related plants) the tissue giving rise to sporangia.
- placement test,
- placenta accreta,
- placenta circumvallata,
- placenta fenestrata,
- placenta increta,
- placenta marginata
Origin of placenta
Examples from the Web for placental
When the ectopic ovum begins to develop in the Fallopian tube the placental villi erode the tubal wall and the blood-vessels.The Ethics of Medical Homicide and Mutilation|Austin O'Malley
These four kinds of omphalosites are either dead when born, or they die as soon as the placental circulation is cut off.Essays In Pastoral Medicine|Austin Malley
But increase in size and activity, and the expense of producing each new individual, led to the adoption of placental development.The Whence and the Whither of Man|John Mason Tyler
A virulent form of fever is not unfrequently occasioned by retained coagula or placental dbris which have undergone decomposition.
Thus the fravashi has the same remarkable associations with nourishment and placental functions as the ka.The Evolution of the Dragon|G. Elliot Smith
noun plural -tas or -tae (-tiː)
- the part of the ovary of flowering plants to which the ovules are attached
- the mass of tissue in nonflowering plants that bears the sporangia or spores
Word Origin for placenta
1808, from Modern Latin placentalis, from placenta (see placenta).
1670s of plants, 1690s of mammals, from Modern Latin placenta uterina "uterine cake" (so called 16c. by Italian anatomist Realdo Colombo), from Latin placenta "a cake, flat cake," from Greek plakoenta, accusative of plakoeis "flat," related to plax (genitive plakos) "level surface, anything flat," from PIE *plak- (1) "to be flat" (cf. Greek plakoeis "flat," Lettish plakt "to become flat," Old Norse flaga "layer of earth," Norwegian flag "open sea," Old English floh "piece of stone, fragment," Old High German fluoh "cliff"), extended form of root *pele- (2) "flat, to spread" (see plane (n.1)). So called from the shape.
n. pl. pla•cen•tas
An organ that forms in the uterus after the implantation of a zygote. The placenta moves nourishment from the mother's blood to the embryo or fetus; it also sends the embryo or fetus's waste products into the mother's blood to be disposed of by the mother's excretory system. The embryo or fetus is attached to the placenta by the umbilical cord. After birth, the placenta separates from the uterus and is pushed out of the mother's body.