placenta

/pləˈsɛntə/

/pləˈsɛntə/

Other forms: placentas; placentae

The organ that provides nourishment to developing fetuses before they're born is called a placenta. Most mammals get their nutrients from their mother through the placenta until birth; then they have to look elsewhere...

The placenta is commonly called the afterbirth, since it's expelled from the mother's body after a baby is born. A placenta has the unique position of acting as a temporary organ, growing along with the fetus (or fetuses) it feeds, but completely unnecessary after birth. Human placentas are round and flat, and maybe that's why they got their name from the Latin for "cake," placenta.

Definitions of placenta

1. noun

   the vascular structure in the uterus of most mammals providing oxygen and nutrients for and transferring wastes from the developing fetus
   types:

   afterbirth

   the placenta and fetal membranes that are expelled from the uterus after the baby is born

   type of:

   vascular structure

   a structure composed of or provided with blood vessels
2. noun

   that part of the ovary of a flowering plant where the ovules form
   type of:

   reproductive structure

   the parts of a plant involved in its reproduction