1. A high administrative official or chief officer, as:
a. Any of several high military or civil officials in ancient Rome.
b. The chief of police of Paris, France.
c. A chief administrative official of a department of France.
d. The administrator in charge of discipline at a Jesuit school.
2. A student monitor or officer, especially in a private school.
[Middle English, from Old French, from Latin praefectus, from past participle of praeficere, to place at the head of : prae-, pre- + facere, to make; see dhē- in the Appendix of Indo-European roots.]
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