tetrarchy

/ˈtɛtrɑːrki/
noun
  1. A form of government in which power is shared by four rulers, especially in ancient Rome.
    • Students in history class learned how the tetrarchy divided the empire into eastern and western halves.
    • The tetrarchy lasted for about twenty years before civil war broke out.
    • Diocletian established the tetrarchy to bring stability to the Roman Empire.
Synonyms
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