The Collaborative International Dictionary of English v.0.48:

Centumvir \Cen*tum"vir\, n.; pl. Centumviri. [L., fr. centum
   hundred + Vir man.] (Rom. Hist.)
   One of a court of about one hundred judges chosen to try
   civil suits. Under the empire the court was increased to 180,
   and met usually in four sections.
   [1913 Webster]