chorion

noun

cho·​ri·​on ˈkȯr-ē-ˌän How to pronounce chorion (audio)
: 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

Examples of chorion in a Sentence

Recent Examples on the Web This is essentially a blood clot that can occur when the outermost membrane surrounding the embryo (the chorion) separates a little from the uterine wall, allowing some blood to pool in that space between the two. Amy Marturana, SELF, 28 Dec. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'chorion.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

New Latin, from Greek, afterbirth

First Known Use

1545, in the meaning defined above

Time Traveler
The first known use of chorion was in 1545

Dictionary Entries Near chorion

Cite this Entry

“Chorion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chorion. Accessed 28 Mar. 2024.

Kids Definition

chorion

noun
cho·​ri·​on ˈkōr-ē-ˌän How to pronounce chorion (audio)
ˈkȯr-
: the outer membrane that surrounds the embryo of reptiles, birds, and mammals and that in mammals with a placenta contributes to the formation of the placenta
chorionic
ˌkōr-ē-ˈän-ik
ˌkȯr-
adjective

Medical Definition

chorion

noun
cho·​ri·​on ˈkōr-ē-ˌän, ˈkȯr- How to pronounce chorion (audio)
: the highly vascular outer embryonic membrane that is associated with the allantois in the formation of the placenta

More from Merriam-Webster on chorion

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