amnios

from WordNet (r) 3.0 (2006)
amnios
    n 1: thin innermost membranous sac enclosing the developing
         embryo of higher vertebrates (reptiles, birds and mammals)
         [syn: {amnion}, {amniotic sac}, {amnios}]
    
from The Collaborative International Dictionary of English v.0.48
Amnios \Am"ni*os\, n.
   Same as {Amnion}.
   [1913 Webster]
    

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