chorion
noun
- the outermost of the two membranes that completely envelop a fetus
- the outer membrane or shell of the eggs of insects and other invertebrates
See chorion in American Heritage Dictionary 4
(kôrˈē-ŏnˌ, kōrˈ-)
noun The outer membrane enclosing the embryo in reptiles, birds, and mammals. In placental mammals it contributes to the development of the placenta.
Related Forms:
- choˌri·onˈic (-ŏnˈĭk) adjective
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