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    Placenta \Pla*cen"ta\, n.; pl. L. {Placent[ae]}, E. {Placentas}.
    [L., a cake, Gr. ? a flat cake, from ? flat, fr. ?, ?,
    anything flat and broad.]
    1. (Anat.) The vascular appendage which connects the fetus
    with the parent, and is cast off in parturition with the
    afterbirth.

    Note: In most mammals the placenta is principally developed
    from the allantois and chorion, and tufts of vascular
    villi on its surface penetrate the blood vessels of the
    parental uterus, and thus establish a nutritive and
    excretory connection between the blood of the fetus and
    that of the parent, though the blood itself does not
    flow from one to the other.

    2. (Bot.) The part of a pistil or fruit to which the ovules
    or seeds are attached.

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