三人执政,三头统治,三人执政之职
Triumvirate \Tri*um"vi*rate\, n. [L. triumviratus: cf. F. triumvirat.] 1. Government by three in coalition or association; the term of such a government. 2. A coalition or association of three in office or authority; especially, the union of three men who obtained the government of the Roman empire.
triumvirate n : a group of three men responsible for public administration or civil authority