- Anatomy, Zoology. the innermost of the embryonic or fetal membranes of reptiles, birds, and mammals; the sac in which the embryo is suspended.
- Zoology. a similar membrane of insects and other invertebrates.
Origin of amnion
Examples from the Web for amnion
Historical Examples of amnion
Amnion: the inner of the two membranes enveloping the embryo.Explanation of Terms Used in Entomology
John. B. Smith
The embryo when about to hatch throws off the egg-shell and amnion in a few seconds.Our Common Insects
Alpheus Spring Packard
Only in the chancel were they protected by sheep's amnion stretched on frames.Pabo, The Priest
The amnion contains a fluid known by the name of liquor amnii.A System of Midwifery
Both it and the stalk of the yolk-sack are enveloped by the amnion (am).The Works of Francis Maitland Balfour, Volume III (of 4)
Francis Maitland Balfour
- the innermost of two membranes enclosing an embryonic reptile, bird, or mammalSee also chorion
Word Origin for amnion
Word Origin and History for amnion
1660s, Modern Latin, from Greek amnion "membrane around a fetus," said to be originally "bowl in which the blood of victims was caught" [Liddell & Scott], which is variously said to be of unknown origin, from ame "bucket," or a diminutive of amnos "lamb."
- The thin, membranous sac filled with a serous fluid in which the embryo or fetus is enclosed and suspended in the uterus.amniotic sac
- A thin, membranous sac filled with a watery fluid (called the amniotic fluid) in which the embryo or fetus of a reptile, bird, or mammal is suspended during prenatal development. Also called amniotic sac