- interregnum (n.)
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- 1580s, from Latin interregnum "an interval between two reigns," literally "between-reign," from inter- "between" (see inter-) + regnum "kingship, dominion, rule, realm," related to regere "to rule, to direct, keep straight, guide" (see regal). In the republic, it meant a vacancy in the consulate. The earlier English noun was interreign (1530s), from French interrègne (14c.).