Found 2 items, similar to amnion.
English → English (WordNet) Definition: amnion amnion n : thin innermost membranous sac enclosing the developing embryo of higher vertebrates (reptiles, birds and mammals) [syn: amniotic sac, amnios] [also: amnia (pl)]
English → English (gcide) Definition: Amnion Amnion \Am"ni*on\, n. [Gr. ? the membrane round the fetus, dim. of ? lamb.] (Anat.) A thin membrane surrounding the embryos of mammals, birds, and reptiles. [1913 Webster]