prefect (n.)

mid-14c., "civil or military official, governor, magistrate," from Old French prefect (12c., Modern French préfet) and directly from Latin praefectus "public overseer, superintendent, director," a title of certain magistrates, noun use of past participle of praeficere "to put in front, to set over, put in authority," from prae "in front, before" (see pre-) + combining form of facere "to make, to do" (from PIE root *dhe- "to set, put").

The spelling has been restored from Middle English prefet. The meaning "administrative head of the Paris police" is from 1800; the sense of "senior pupil designated to keep order in an English school" is by 1864. Related: Prefectorial; prefectoral.