chorio-

American  

1. a combining form meaning “chorion,” “choroid,” used in the formation of compound words.

   chorioallantois.

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Usage

What does chorio- mean? Chorio- is a combining form used like a prefix meaning either “chorion” or "choroid." It is often used in scientific terms, especially in anatomy and biology. The chorion is the outermost membrane surrounding the embryo of a reptile, bird, or a mammal, and which contributes to the formation of the placenta in mammals, including humans. Choroid means “like the chorion,” but it can also refer to the choroid coat, the vascular layer of the eye. Chorio- comes from the Greek chórion, meaning “the outer membrane of the fetus.”What are variants of chorio-?When combined with words or word elements that begin with a vowel, chorio- becomes chori-, as in chorioma. Related to chorio- are the combining forms choroido- and chorioido-, specifically used to represent the choroid coat.

Etymology

Origin of chorio-

Combining form representing Greek chórion