placenta

[ pluh-sen-tuh ]

noun

, plural pla·cen·tas, pla·cen·tae [pl, uh, -, sen, -tee].

1. Anatomy, Zoology. 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.
2. Botany.
   1. the part of the ovary of flowering plants that bears the ovules.
   2. (in ferns and related plants) the tissue giving rise to sporangia.

placenta

/ pləˈsɛntə /

noun

1. the vascular organ formed in the uterus during pregnancy, consisting of both maternal and embryonic tissues and providing oxygen and nutrients for the fetus and transfer of waste products from the fetal to the maternal blood circulation See also afterbirth
2. the corresponding organ or part in certain mammals
3. botany
   1. the part of the ovary of flowering plants to which the ovules are attached
   2. the mass of tissue in nonflowering plants that bears the sporangia or spores

placenta

/ plə-sĕn′tə /

1. The sac-shaped organ that attaches the embryo or fetus to the uterus during pregnancy in most mammals. Blood flows between mother and fetus through the placenta, supplying oxygen and nutrients to the fetus and carrying away fetal waste products. The placenta is expelled after birth.
2. The part of the ovary of a flowering plant to which the ovules are attached. In a green pepper, for example, the whitish tissue to which the seeds are attached is the placenta.

placenta

1. 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.

Other Words From

• pla·cental plac·en·tar·y [plas, -, uh, n-ter-ee, pl, uh, -, sen, -t, uh, -ree], adjective
• inter·pla·cental adjective
• nonpla·cental adjective
• prepla·cental adjective
• subpla·centa noun plural subplacentas subplacentae
• subpla·cental adjective

Word History and Origins

Origin of placenta¹

First recorded in 1670–80; from New Latin: “something having a flat, circular form,” Latin: “cake,” from Greek plakóenta, accusative of plakóeis “flat cake,” derivative of pláx (stem plak- ) “flat”

Word History and Origins

Origin of placenta¹

C17: via Latin from Greek plakoeis flat cake, from plax flat

Example Sentences

She was blue and didn’t seem to be breathing at first while she was still connected to the placenta, which Downing said is normal.

From Los Angeles Times

All medications pass the placenta, and many will reach the brain of the fetus, said Veerle Bergink, director of Mount Sinai’s Women’s Mental Health Center in New York.

From Salon

“The antibodies have to cross the placenta,” and that takes time.

From Los Angeles Times

For this purpose, the team used fully functional human placentas that were made available after planned caesarean sections.

From Science Daily

The placenta, the new organ that forms to nourish the fetus, presents new receptors for the disease to bind to.

From Salon

Related Words

• sheath
• sheet