The Collaborative International Dictionary of English v.0.48:
Prefect \Pre"fect\, n. [L. praefectus, fr. praefectus, p. p. of
praeficere to set over; prae before + facere to make: cf. F.
1. A Roman officer who controlled or superintended a
particular command, charge, department, etc.; as, the
prefect of the aqueducts; the prefect of a camp, of a
fleet, of the city guard, of provisions; the pretorian
prefect, who was commander of the troops guarding the
2. A superintendent of a department who has control of its
police establishment, together with extensive powers of
municipal regulation. [France] --Brande & C.
3. In the Greek and Roman Catholic churches, a title of
certain dignitaries below the rank of bishop.
Apostolic prefect (R. C. Ch.), the head of a mission, not
of episcopal rank. --Shipley.