amnion
NounOpen English WordNet
Noun (1)amnia
- thin innermost membranous sac enclosing the developing embryo of higher vertebrates (reptiles, birds and mammals)Synonyms: amniotic sacamniosType of sacPart of amniote, fetal membrane
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mundaneadjective
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Webster's Dictionary (1913)
Am′ni·on (…), noun
Origin: Gr. … the membrane round the fetus, dim. of … lamb.
Anatomy A thin membrane surrounding the embryos of mammals, birds, and reptiles.
Webster’s Revised Unabridged Dictionary (1913), from GCIDE 0.54