Middle English word prothonotarie comes from Ancient Greek πρῶτον, Latin notarius

Detailed word origin of prothonotarie

Dictionary entry	Language	Definition
πρῶτον	Ancient Greek (grc)
notarius	Latin (lat)	Clerk, secretary; writer of shorthand; stenographer. Notary.
protonotarius	Late Latin (LL)
prothonotarius	Malayalam (mal)
prothonotarie	Middle English (enm)