among the Romans, an officer in the infantry, who commanded a century, or a hundred men.
In order to have a proper notion of the centurions, it must be remembered, that every one of the thirty manipuli * in a legion was divided into two ordines, or centuries; and consequently the three bodies of the ha-nipulati, principes, and triarii, into 20 orders a piece, as into 10 manipuli. Now, every manipulus was allowed two centurions, or captains, one to each order or century; and, to determine the point of priority between them, they were created at two different elections. The 30 who were made first always took the precedence of their fellows; and therefore commanded the right-hand orders, as the others did the left. The triarii, Centurion or pilani, so called from their weapon the pilum, being esteemed the most honourable, had their centurions elected first, next to them the principes, and afterwards the haflati; whence they were called primus et secundus pilum, primus et secundus princeps, primus et secundus haflatus; and so on. Here it may be observed, that primi ordines is sometimes used in historians for the centurions of these orders; and the centurions are sometimes styled principes ordinum, and principes centurionum.
We may take notice too what a large field there lay for promotion: first through all the orders of the haflati; then quite through the principes; and afterwards from the last order of the triarii to the primipilus, the most honourable of the centurions, and who deserves to be particularly described. This officer, besides his title of primipilus, went under the several titles of dux legionis, praefectus legionis, primus centurionum, and primus centurio; and was the first centurion of the triarii in every legion. He presided over all the other centurions, and generally gave the word of command by order of the tribunes. Besides this he had the care of the eagle or chief standard of the legion: hence, aquila praefecta, is to bear the dignity of primipilus; and hence aquila is taken by Pliny for the said office.
Nor was this station only honourable, but very profitable too: for he had a special stipend allowed him, probably as much as a knight's estate; and, when he left that charge, was reputed equal to the members of the equitrian order, bearing the title of primipilarius, in the same manner as those who had discharged the greatest civil offices were styled ever after, consulares, censores, &c.