pre·fect / ˈprēˌfekt/ • n. a chief officer, magistrate, or regional governor in certain countries: the prefect of police. ∎  a senior magistrate or governor in the ancient Roman world: Avitus was prefect of Gaul from AD 439.DERIVATIVES: pre·fec·tor·al / prēˈfektərəl/ adj.pre·fec·to·ri·al / ˌprēˌfekˈtôrēəl/ adj.

prefect governor, chief administrator. XIV. — OF. prefect (mod. préfet) — L. præfectus, sb. use of pp. of præficere set over, f. præ- PRE- + facere make, constitute.
So prefecture XVI. — (O)F. or L.