quindecemvir
/ˌkwɪndɪˈsɛmvə/(also quindecimvir) Roman History
noun
A member of a group consisting of fifteen people (usually men); specifically one of the body of fifteen priests who had charge of the Sibylline books.
Origin
Early 17th century; earliest use found in Philemon Holland (1552–1637), translator. From classical Latin quīndecimvir (originally in plural quīndecimvirī; in post-classical Latin also quindecemvir, e.g. in 16th-cent. editions of Pliny) from quīndecim fifteen (from quīnque five + decem ten, with syncope of medial syllable) + vir man.