allantoamnionic

adjective

al·​lan·​to·​am·​ni·​on·​ic

variants or allantoamniotic

ə¦lan(ˌ)tōˌ⸗⸗¦⸗⸗

: relating to the allantois and amnion especially when fused into a single membrane compare chorioallantois

Word History

Etymology

allant- + amnionic or amniotic

First Known Use

1947, in the meaning defined above

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