Also found in: Thesaurus, Medical, Encyclopedia, Wikipedia.
Related to placental: Placental abruption, placental insufficiency, placental calcification, Placental mammals
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.]
(Zoology) (esp of animals) having a placenta: placental mammals. See also eutherian
Switch to new thesaurus
|Noun||1.||placental - 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
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
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
plantigrade, plantigrade mammal - an animal that walks with the entire sole of the foot touching the ground as e.g. bears and human beings
|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"
a. placentario-a, de la placenta.