1. Roman law. An absolute ruler appointed in an emergency for a term of six months and subject to reappointment.
“In special emergencies, particularly in times of grave crisis, either consul might appoint a dictator who exercised supreme authority, but not beyond six months, unless reappointed. This was, in effect, a temporary reversion to monarchy.” R.W. Lee, The Elements of Roman Law 14 (4th ed. 1956).
2. A person, esp. a ruler, with absolute authority.