Amnion
/ˈæm.ni.ən/noun
The innermost membrane surrounding an embryo or fetus, enclosing the amniotic fluid.
Did you know?The Greek term likely referred to a bowl or vessel, creating a striking image of the amnion as a natural container holding and protecting developing life.
Etymological Timeline
Ancient Greek
Greek
ἀμνίον (amnion)
“A small bowl or vessel; later, the membrane surrounding a fetus”
Hellenistic Greek
Greek
ἀμνίον
“A membrane enclosing the fetus, understood metaphorically or descriptively as a container”
2nd Century CE
Latin
amnion
“The fetal membrane”
16th Century
Neo-Latin
amnion
“An anatomical term for the innermost fetal membrane”
17th Century
English
amnion
“The membrane enclosing an embryo or fetus”
Modern English
English
amnion
“The innermost fetal membrane containing amniotic fluid”