[kawr-ee-on, kohr-] /ˈkɔr iˌɒn, ˈkoʊr-/
Embryology. the outermost of the extraembryonic membranes of land vertebrates, contributing to the formation of the placenta in the placental mammals.
Zoology. the membrane around the eggs of certain insects, secreted by cells of the ovary.
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
“outer membrane of the fetus,” 1540s, medical Latin, from Greek khorion “membrane enclosing the fetus, afterbirth,” perhaps from PIE *ghere- “gut, entrail” (see yarn).
chorion cho·ri·on (kôr’ē-ŏn’)
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.
The outer membrane that encloses the embryo of a reptile, bird, or mammal. In mammals, the chorion contributes to the development of the placenta.
- Chorionic epithelioma
chorionic epithelioma n. See choriocarcinoma.
noun 1. Also called human chorionic gonadotropin. Biochemistry. a hormone, produced in the incipient placenta of pregnant women, that stimulates the production of estrogen and progesterone: its presence in blood or urine is an indication of pregnancy. 2. Pharmacology. a commercial form of this substance, obtained from the urine of pregnant mares, used in medicine […]
- Chorionic growth hormone-prolactin
chorionic growth hormone-prolactin n. See human placental lactogen.
noun, Embryology. 1. one of the branching outgrowths of the chorion that, together with maternal tissue, form the placenta. chorionic villus n. Any of the various fingerlike projections of the chorion of the embryo that contain fetal blood vessels and grow into the intervillous lacuna of the placenta.