ˈkōrēˌän, -ȯr-, -ēən noun
( -s )
Etymology: New Latin, from Greek
1. : the highly vascular outer embryonic membrane of higher vertebrates (reptiles, birds, and mammals) that in the more advanced placental mammals is associated with the allantois in the formation of the placenta and is commonly separable into (1) a villous part that enters into the placenta and (2) a smooth part that does not — called also respectively (1) chorion frondosum and (2) chorion laeve ; see amnion
2. : any of various envelopes (not homologous with the chorion of mammals) of the eggs of different animals ; especially : a membrane of the eggs of many insects secreted by the follicular cells surrounding the egg in the ovary
• cho·ri·on·ic | ̷ ̷ ̷ ̷|änik adjective