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The outer membrane enclosing the embryo in reptiles, birds, and mammals. In placental mammals it contributes to the development of the placenta.
cho′ri·on′ic (-ŏn′ĭk) adj.
(Anatomy) the outer of two membranes that form a sac around the embryonic reptile, bird, or mammal: contributes to the placenta in mammals. See also amnion
[C16: from Greek khorion afterbirth]
ˌchoriˈonic, ˈchorial adj
cho•ri•on(ˈkɔr iˌɒn, ˈkoʊr-)
1. the outermost of the membranes enclosing the embryo in reptiles, birds, and mammals, developing into part of the eggshell or part of the placenta.
2. a membrane enclosing the shell of an insect egg.
[1535–45; < Greek chórion afterbirth]
cho`ri•on′ic, cho′ri•al, adj.
The outer membrane that encloses the embryo of a reptile, bird, or mammal. In mammals, the chorion contributes to the development of the placenta.
The embryo’s outer membrane, which helps to form the placenta.
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|Noun||1.||chorion - the outermost membranous sac enclosing the embryo in higher vertebrates (reptiles, birds and mammals)|
amniote - any member of the Amniota
chorionic villus - one of the tiny villi that stick out of the fetal chorion and combine with the mother's uterine tissue to form the placenta
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
fetal membrane - any membrane that functions for the protection or nourishment or respiration or excretion of a developing fetus
sac - a structure resembling a bag in an animal
n. corión, una de las dos membranas que rodean al feto.