n.
Pronunciation: ˌ ko ̇ r- ē -( ˌ ) ō - ə - ' lan-t ə -w ə s
Function: noun
Etymology: New Latin, from Greek chorion + New Latin allantois
Date: 1933
: a vascular fetal membrane composed of the fused chorion and adjacent wall of the allantois that in the hen's egg is used as a living culture medium for viruses and for tissues ― called also chorioallantoic membrane
– cho · rio · al · lan · to · ic \ - ˌ a-l ə n- ' t ō -ik \ adjective