Definition of triumvir in US English:



  • (in ancient Rome) each of three public officers jointly responsible for overseeing any of the administrative departments.

    • ‘The system was revived later in the century by the triumvirs Mark Antony, Marcus Lepidus and Octavian to eliminate those judged sympathetic to the assassination of Julius Caesar.’
    • ‘For a time, he simply continued by virtue of the powers he had won as a triumvir.’
    • ‘After Julius Caesar's assassination, the triumvirs was formed, consisting of three determined men, Octavius Caesar, Mark Antony, and Lepidus, who shared the rule of the Roman Empire.’
    • ‘Political anarchy reigned in Rome at the hands of the triumvirs.’
    • ‘Octavius, nephew of Julius Caesar, Antony, and Lepidus, united as triumvirs, oppose the forces raised by Brutus and Cassius.’


Latin, originally as triumviri (plural), back-formation from trium virorum ‘of three men’, genitive of tres viri.