I.primus: primus pilus (in the gen. written also as one word, primipili), the division of the triarii in the Roman army: “P. Sextius Baculus, primi pili centurio,” Caes. B. G. 3, 5; id. B. C. 1, 13: T. Balventius, qui superiore anno primum pilum duxerat, had been leader, captain of the triarii, id. B. G. 5, 35; Liv. 42, 34, 11: aliquem ad primum pilum transducere, to transfer, advance to the triarii, Caes. B. C. 3, 53, 5: primos pilos ademit, took the command of the triarii, of the primipili, Suet. Calig. 44: “vetus consuetudo tenuit, ut ex primo principe legionis promeretur centurio primi pili, qui non solum aquilae praeerat, verum etiam quatuor centurias in primā acie gubernabat,” Veg. Mil. 2, 8.—Without primus: “referes pili praemia,” Mart. 6, 58, 10; 1, 32, 3.—
II. Transf.: primipilus (in inscrr. also written PRIMOPIL, and abbrev. P. P.), the chief centurion of the triarii (the transf. arose from the circumstance that the chief centurion of this division was originally designated by the term primi pili, with the omission of the easily supplied centurio, as is shown by the following citation from Liv. 7, 41, 5; “soon, however, from primi pili, a new word, primipilus or primopilus, was formed): primus centurio erat, quem nunc primi pili appellant,” Liv. 7, 41, 5; 8, 8, 16: “primipilo P. Sext. Baculo vulneribus confecto,” Caes. B. G. 2, 25: “aquilarum altera vix convelli a primipilo potuit,” Val. Max. 1, 6, 11; Inscr. (of the time of Trajan) Orell. 799: SEX. AVLIENO SEX. F. PRIMOPIL. II., Inscr. (of the time of Tiberius or Caligula) Orell. 3426 M. P.; cf. Becker, Antiq. 3, 3, p. 264.
