A thin membrane surrounding the embryos of animals birds and reptiles
- thin innermost membranous sac enclosing the establishing embryo of higher vertebrates (reptiles, wild birds and animals)
- A thin membrane layer surrounding the embryos of mammals, birds, and reptiles.
a thin membrane that surrounds the fetus during maternity. The amnion could be the internal associated with the two fetal membranes (the chorion may be the exterior one), and it also contains the amniotic liquid.
1660s, contemporary Latin, from Greek amnion "membrane around a fetus," reported to be originally "bowl where bloodstream of victims was caught" [Liddell & Scott], that is variously considered of as yet not known source, from ame "bucket," or a diminutive of amnos "lamb."
The membrane layer inside uterus that's closest towards fetus; generally known as the amniotic sac.
(n.) A thin membrane layer surrounding the embryos of mammals, wild birds, and reptiles.
Wheeler, the amnion is ruptured and turned back from covering the germ band, enclosing the yolk dorsally and becoming finally absorbed, as the ectoderm of the germ band itself spreads to form the dorsal wall.