Amniotic
来自Big Physics
early 19th century: formed irregularly from obsolete amnios ‘amnion’ + -otic, perhaps via French amniotique .
wiktionary
Likely borrowed from French amniotique. Equivalent to amnion + -otic.
etymonline
amniotic (adj.)
1822, from amnion + -ic, perhaps from or based on French amniotique. The form is irregular; a classically correct word would be *amniac.
