Medical dictionary

Chorion

Chorion: The outermost of the two fetal membranes—the amnion is the innermost —. which together surround the embryo. The chorion develops villi (vascular fingers) and gives rise to the placenta. In Greek, the word "chorion" means "skin or leather."
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The multilayered, outermost fetal membrane consisting of extraembryonic somatic mesoderm, trophoblast, and, on the maternal surface, villi bathed by maternal blood; as pregnancy progresses, part of the c. becomes the definitive fetal placenta. SYN: chorionic sac, membrana serosa (1). [G. c., membrane enclosing the fetus]

- c. frondosum the part of the c. where the villi persist, forming the fetal part of the placenta. SYN: shaggy c..

- c. laeve the portion of the c. from which the villi disappear in the later stages of pregnancy. SYN: smooth c..

- previllous c. SYN: primitive c..

- primitive c. the c. before its villi are well formed. SYN: previllous c..

- shaggy c. SYN: c. frondosum.

- smooth c. SYN: c. laeve.

Chorion — Cho ri*on, n. [NL., fr. Gr. ?.] 1. (Anat.) (a) The outer membrane which invests the fetus in the womb; also, the similar membrane investing many ova at certain stages of development. (b) The true skin, or cutis. [1913 Webster] 2. (Bot.) The outer … The Collaborative International Dictionary of English
chorion — 1> биол. хорион, яйцевая или наружная оболочка … Новый большой англо-русский словарь
chorion — chorion. См. хорион. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.
Chorion — Chorion, Haut, die Hülle der Leibesfrucht mit Ausschluß der innersten der Schafhaut (vergl. Amnion, Embryo, Fötus) … Herders Conversations-Lexikon

Chorion — For the chorion in invertebrate eggs, see Chorion (egg). Chorion Diagram showing earliest observed stage of human embryo … Wikipedia
Chorion — 1.Le chorion, nom grec du placenta, est l enveloppe la plus externe de l œuf. Chez les mammifères, il est en contact avec les tissus maternels. La nature du chorion varie suivant la période de la grossesse. 2.Le chorion définit aussi le tissu… … Wikipédia en Français
chorion — chorionic, chorial, adj. /kawr ee on , kohr /, n. 1. Embryol. the outermost of the extraembryonic membranes of land vertebrates, contributing to the formation of the placenta in the placental mammals. 2. Zool. the membrane around the eggs of… … Universalium
chorion — хорион (биология) хорион, яйцевая или наружная оболочка … Большой англо-русский и русско-английский словарь
chorion — noun Etymology: New Latin, from Greek, afterbirth Date: 1545 the highly vascular outer embryonic membrane of reptiles, birds, and mammals that in placental mammals is associated with the allantois in the formation of the placenta … New Collegiate Dictionary