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n. pl. pla·cen·tas or pla·cen·tae (-tē)
a. A membranous vascular organ that develops in female eutherian mammals during pregnancy, lining the uterine wall and partially enveloping the fetus, to which it is attached by the umbilical cord. Following birth, the placenta is expelled.
b. A similar organ in marsupial mammals, consisting of a yolk sac attached to the uterine wall.
c. An organ with similar functions in some nonmammalian animals, such as certain sharks and reptiles.
2. Botany The part within the ovary of a flowering plant to which the ovules are attached.

[New Latin, from Latin, flat cake, alteration of Greek plakoenta, from accusative of plakoeis, flat, from plax, plak-, flat land, surface; see plāk- in Indo-European roots.]

pla·cen′tal adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(pləˈsɛntəl) or


(Zoology) (esp of animals) having a placenta: placental mammals. See also eutherian
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.placental - mammals having a placentaplacental - mammals having a placenta; all mammals except monotremes and marsupials
mammal, mammalian - any warm-blooded vertebrate having the skin more or less covered with hair; young are born alive except for the small subclass of monotremes and nourished with milk
Eutheria, subclass Eutheria - all mammals except monotremes and marsupials
farm animal, livestock, stock - any animals kept for use or profit
bull - mature male of various mammals of which the female is called `cow'; e.g. whales or elephants or especially cattle
cow - mature female of mammals of which the male is called `bull'
yearling - an animal in its second year
buck - mature male of various mammals (especially deer or antelope)
doe - mature female of mammals of which the male is called `buck'
insectivore - small insect-eating mainly nocturnal terrestrial or fossorial mammals
aquatic mammal - whales and dolphins; manatees and dugongs; walruses; seals
carnivore - a terrestrial or aquatic flesh-eating mammal; "terrestrial carnivores have four or five clawed digits on each limb"
Fissipedia - in some classifications considered a suborder of Carnivora
aardvark, Orycteropus afer, ant bear, anteater - nocturnal burrowing mammal of the grasslands of Africa that feeds on termites; sole extant representative of the order Tubulidentata
bat, chiropteran - nocturnal mouselike mammal with forelimbs modified to form membranous wings and anatomical adaptations for echolocation by which they navigate
gnawing mammal, lagomorph - relative large gnawing animals; distinguished from rodents by having two pairs of upper incisors specialized for gnawing
gnawer, rodent - relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing
Ungulata - in former classifications a major division of Mammalia comprising all hoofed mammals; now divided into the orders Perissodactyla (odd-toed ungulates) and Artiodactyla (even-toed ungulates)
hoofed mammal, ungulate - any of a number of mammals with hooves that are superficially similar but not necessarily closely related taxonomically
Unguiculata - in former classifications a major division of Mammalia comprising mammals with nails or claws; distinguished from hoofed mammals and cetaceans
unguiculate, unguiculate mammal - a mammal having nails or claws
cony, das, dassie, hyrax, coney - any of several small ungulate mammals of Africa and Asia with rodent-like incisors and feet with hooflike toes
pachyderm - any of various nonruminant hoofed mammals having very thick skin: elephant; rhinoceros; hippopotamus
edentate - primitive terrestrial mammal with few if any teeth; of tropical Central America and South America
anteater, pangolin, scaly anteater - toothless mammal of southern Africa and Asia having a body covered with horny scales and a long snout for feeding on ants and termites
primate - any placental mammal of the order Primates; has good eyesight and flexible hands and feet
tree shrew - insectivorous arboreal mammal of southeast Asia that resembles a squirrel with large eyes and long sharp snout
colugo, flying cat, flying lemur - arboreal nocturnal mammal of southeast Asia and the Philippines resembling a lemur and having a fold of skin on each side from neck to tail that is used for long gliding leaps
proboscidean, proboscidian - massive herbivorous mammals having tusks and a long trunk
plantigrade, plantigrade mammal - an animal that walks with the entire sole of the foot touching the ground as e.g. bears and human beings
digitigrade, digitigrade mammal - an animal that walks so that only the toes touch the ground as e.g. dogs and cats and horses
Adj.1.placental - pertaining to or having or occurring by means of a placenta; "all mammals except monotremes and marsupials are placental mammals"
aplacental - having no placenta; "monotremes and marsupials are aplacental mammals"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


a. placentario-a, de la placenta.
English-Spanish Medical Dictionary © Farlex 2012


adj placentario; — abruption desprendimiento prematuro de placenta
English-Spanish/Spanish-English Medical Dictionary Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
References in periodicals archive ?
Pandey, "A trial to determine the role of placental extract in the treatment of chronic non-healing wounds," Journal of Wound Care, vol.
In more advanced pregnancies, indications for a cytogenetic workup may include congenital anomalies and/or placental dysmorphology.
The histological changes in preeclamptic/eclamptic placentas include infarcts, increased syncytial knots, hypovascularity of the villi, cytotrophoblastic proliferation, thickening of the trophoblastic membrane, obliterative enlarged endothelial cells in the fetal capillaries, and atherosis of the spiral arteries in the placental bed [11].
As a response to IUGR, placental perfusion decreases due to placental insufficiency and eventually fetal Doppler ultrasonography (US) and fetal biometry are affected (2-4).
One of the most common placental abnormalities is abruptio placenta; this Latin term is explained as 'rending asunder of the placenta', implying and denoting a sudden accident1.
JERUSALEM, Israel, May 2, 2019 -- In work that may have significant implications for modeling embryonic disease and placental dysfunctions, researchers here have found a way to transform skin cells into the three major stem cell types that comprise early-stage embryos.
The concept of maternal placental syndromes encompasses four events believed to originate from diseased placental blood vessels: preeclampsia, gestational hypertension, placental abruption, and placental infarction.
LAHORE -- A civil court has issued a notice to a private hospital on a Rs10 million damages suit filed by a woman for spoiling specimen of her placental tissues collected during a dilation and curettage (DandC) procedure.
The placental-to-birth weight ratio (PFR) has been used as a proxy measure of placental efficiency with the common idea that decreased PFR reflects increased placental activity and nutrient transfer capacity, whereas increased PFR indicates less efficient placenta (Hayward et al.
The umbilical cord is inserted in most cases in this part of the placenta in a slightly eccentric position, but there are other types of insertion such as marginal cord insertion, where the cord is attached to the side, or velamentous cord insertion, where the umbilical vessels are separated in the membranes at a certain distance from the placental margin, where they arrive surrounded only by a fold in the amnion.
GDM has also been shown to be associated with placental abnormalities including altered placental function, oxidative stress, and vascular dysfunction.