Placental

pla·cen·ta  (pl-snt)

n. pl. pla·cen·tas or pla·cen·tae (-t)

1.

a. A membranous vascular organ that develops in female 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. 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.

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[New Latin, from Latin, flat cake, alteration of Greek plakoenta, from accusative of plakoeis, flat, from plax, plak-, flat land, surface; see plk-¹ in Indo-European roots.]

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pla·cental adj.

Thesaurus

Noun	1.	placental - mammals having a placenta; all mammals except monotremes and marsupials eutherian, eutherian mammal, placental mammal 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"