noun🔗ShareAmniosThe innermost membrane of the fetal membranes of reptiles, birds, and mammals; the sac in which the embryo is suspended."The doctor explained that the amnion, a protective sac filled with fluid, cushions the baby inside the womb. "El médico explicó que el amnios, un saco protector lleno de líquido, amortigua al bebé dentro del útero.biologyanatomymedicineorganorganismChat with AIVocabulary GamePractice Reading