n. pl. tri·um·virs or tri·um·vi·ri (-və-rī′)
1. One of three men sharing public administration or civil authority in ancient Rome.
2. One of three people sharing public administration or civil authority.
[Middle English, from Latin, back-formation from triumvirī, board of three, from trium virum, of three men : trium, genitive pl. of trēs, three; see trei- in the Appendix of Indo-European roots + virum, archaic genitive pl. of vir, man; see wī-ro- in the Appendix of Indo-European roots.]
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