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.
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How to use amnion in a sentence
Between these is a gelatinous substance, and within the amnion is a fluid, called the liquor amnii.
The whole being surrounded by two membranous coverings, the outer one called the chorion, and the inner one the amnion.
The amnion forms a small fold covering over the cephalic extremity of the embryo, which is deeply embedded in the yolk.The Works of Francis Maitland Balfour, Volume 1 | Francis Maitland Balfour
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
It adheres to the amnion and supplies it with blood-vessels (Bischoff).The Works of Francis Maitland Balfour, Volume III (of 4) | Francis Maitland Balfour
British Dictionary definitions for amnion
the innermost of two membranes enclosing an embryonic reptile, bird, or mammal: See also chorion
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for amnion
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
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.