from
The Collaborative International Dictionary of English v.0.48
Triumvir \Tri*um"vir\, n.; pl. L. {Triumviri}, E. {Triumvirs}.
[L., fr. res, gen. trium, three + vir a man. See {Three}, and
{Virile}.] (Rom. Antiq.)
One of tree men united in public office or authority.
[1913 Webster]
Note: In later times the triumvirs of Rome were three men who
jointly exercised sovereign power. Julius Caesar,
Crassus, and Pompey were the first triumvirs;
Octavianus (Augustus), Antony, and Lepidus were the
second and last.
[1913 Webster]