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Medical Dictionary

allantois

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noun al·lan·to·is \ə-ˈlant-ə-wəs\

Medical Definition of allantois

plural al·lan·to·ides \ˌal-ən-ˈtō-ə-ˌdēz, ˌal-ˌan-\play play

  1. :  a vascular fetal membrane of reptiles, birds, or mammals that is formed as a pouch from the hindgut and that in placental mammals is intimately associated with the chorion in formation of the placenta




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