ἡγεμονία, ἡγεμονίας, ἡ (ἡγεμών) (Herodotus, Thucydides, Plato, others), chief command, rule, sovereignty: of the reign of a Roman emperor, Luke 3:1; Josephus, Antiquities 18, 4, 2.
Luke 3:1 - N-GFS GRK:πεντεκαιδεκάτῳ τῆς ἡγεμονίας Τιβερίου Καίσαρος NAS: year of the reign of Tiberius KJV: year of the reign of Tiberius INT: fifteenth of the reign of Tiberius Ceasar