Allantoidea

plural noun

Al·​lan·​toi·​dea

ˌalən‧ˈtȯidēə,

ˌaˌlan‧-;

əˌlantəˈwidēə

in some classifications

: a division of Vertebrata comprising all forms in which the embryo develops a complete allantois

Word History

Etymology

New Latin, from allantoid-, allantois

First Known Use

1860, in the meaning defined above

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