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Pronunciation: ko're-on

Definition: The outermost fetal membrance in human embryos, the villous part of which becomes the fetal part of the placenta.

Synonym(s): membrana serosa1

[G. chorion, membrane enclosing the fetus]

Further information

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.