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2. dĕcŭrĭo, ōnis (also DECURES decuriones, Paul. ex Fest. p. 71, 22, and 75, 9 Müll.; and DECVRIONVS, the same, ib. 49, 16), m. [decuria], the head or chief of a decuria, a decurion. The name was first given by Romulus to the head of the tenth part of a curia (cf. Nieb. Röm. Gesch. 1, p. 354). In the army, the commander of a decuria of cavalry, Varr. L. L. 5, § 91 Müll.; Veget. Mil. 2, 14; Caes. B. C. 1, 23; 1, 13; Tac. A. 13, 40; id. H. 2, 29. After the extension of the Roman dominion, the members of the senate of the municipia and the colonies were called decuriones, Dig. 50, 16, 239; 50, 2; Cod. Just. 10, 31; Cic. Sest. 4, 10; id. Rosc. Am. 9, 25; id. Clu. 14, 41; Vulg. Marc. 15, 43.
Sometimes i. q. praefectus, applied to the overseer of the persons employed in any duty about the court, e. g. a head-chamberlain: cubiculariorum, Suet. Dom. 17, PROCVLVS DECVRIO GERMANORVM (i. e. custodum corporis) TI. GERMANICI, Inscr. Orell. 2923.