placenta

noun
pla·cen·ta | \plə-ˈsen-tə \
plural placentas or placentae\plə-ˈsen-(ˌ)tē \

Definition of placenta 

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

Examples of placenta in a Sentence

Recent Examples on the Web

In the photo, Van Der Beek is sitting on the ground with his baby in his arms and a placenta placed in a mixing bowl in front of him. Jennifer Earl, Fox News, "James Van Der Beek shares photo of wife's placenta: 'Word of caution, if you’re squeamish'," 19 June 2018 That blood bears free-floating fragments of genetic material (RNA) from the fetus, mother and placenta, which can provide a glimpse into fetal development. Dina Fine Maron, Scientific American, "Blood Test Could Predict Premature Birth Risk, Due Date," 7 June 2018 Every tissue in the body — including the placenta and fetus during pregnancy — contributes cell-free RNA to the bloodstream, said Stephen Quake, the paper’s senior author and a professor of bioengineering and applied physics at Stanford. Karen Weintraub, STAT, "Blood test might help predict both preterm and healthy delivery dates," 7 June 2018 Images capture blood, vulvas, placenta, areola, crowning shots, and inaugural breastfeeding. Allison Yarrow, Harper's BAZAAR, "The Childbirth Photos Instagram Didn't Want You to See," 11 May 2018 The researchers studied genes linked to the placenta, the maternal immune system and the fetal liver, and found nine of those genes produce RNA signals that change distinctly as pregnancy progresses. Pam Belluck, New York Times, "Blood Test Might Predict Pregnancy Due Date and Preterm Birth," 7 June 2018 After giving birth, your placenta is supposed to come out. Rachel Epstein, Marie Claire, "Kim Kardashian Posts a Sweet Picture of Saint Snuggling Chicago," 22 May 2018 Toxoplasma courses through the body, targeting any combination of organs, including, in the case of females, the uterus, and for fetuses, the placenta. Kim Steutermann Rogers, Smithsonian, "How the Tiniest of Parasites is Taking Down the Mightiest of Monk Seals," 9 July 2018 To make these new experimental blood tests, the Quake team identified and zeroed in on the activity levels of specific genes in the fetus or its placenta. Dina Fine Maron, Scientific American, "Blood Test Could Predict Premature Birth Risk, Due Date," 7 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'placenta.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of placenta

1638, in the meaning defined at sense 1

History and Etymology for placenta

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

Keep scrolling for more

Learn More about placenta

Statistics for placenta

Last Updated

8 Oct 2018

Look-up Popularity

Time Traveler for placenta

The first known use of placenta was in 1638

See more words from the same year

Keep scrolling for more

More Definitions for placenta

placenta

noun

English Language Learners Definition of placenta

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

noun
pla·cen·ta | \plə-ˈsen-tə \

Kids Definition of placenta

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

placenta

noun
pla·cen·ta | \plə-ˈsent-ə \
plural placentas or placentae\-ˈsent-(ˌ)ē \

Medical Definition of placenta 

: 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

Keep scrolling for more

Comments on placenta

What made you want to look up placenta? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

one that holds something together

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Roman Mythology Quiz

  • the-triumph-of-venus-by-alessandro-magnasco
  • Boreal comes from the name of the ancient Greek god of which wind?
True or False

Test your knowledge - and maybe learn something along the way.

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!