▪ I. pentarch, n.
(ˈpɛntɑːk)
[ad. Gr. type πένταρχος (used in Byzant. Gr.), f. πέντ(ε five + -αρχος ruler: cf. tetrarch. In mod.F. pentarque (Littré).]
a. The ruler of one of a group of five districts or kingdoms. b. One of a governing body of five persons.
| [1656 Blount Glossogr., Pentarck..a Captain of five men.] 1793 J. Hely tr. O'Flaherty's Ogygia I. 62 None of the pentarchs under that title assumed the dominion of the whole island [Ireland]. 1798 W. Taylor in Monthly Rev. XXVII. 500 To substitute a monarch for the pentarchs of the present constitution. |
▪ II. ˈpentarch, a. Bot.
[mod. f. Gr. πέντ(ε five + άρχή beginning.]
Arising from five distinct points of origin, as the woody tissue of a root.
| 1884 Bower & Scott De Bary's Phaner. 348 The xylem is triarch to pentarch and octarch. |