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am·ni·on | \ ˈam-nē-ˌän 
, -ən \
, -ən \ plural amnions or amnia\ ˈam-nē-ə \
\Definition of amnion
1 : a thin membrane forming a closed sac about the embryos or fetuses of reptiles, birds, and mammals and containing the amniotic fluid
2 : a membrane analogous to the amnion and occurring in various invertebrates
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Other Words from amnion
amniotic \ ˌam-nē-ˈä-tik \ adjective
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More Definitions for amnion
amnion
nounam·ni·on | \ ˈam-nē-ˌän, -ən \
\ plural amnions or amnia\ -nē-ə \
\Medical Definition of amnion
: a thin membrane forming a closed sac about the embryos and fetuses of reptiles, birds, and mammals and containing the amniotic fluid
— called also amniotic sac
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Time Traveler for amnion
The first known use of amnion was in 1661
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