in Roman antiquity, ten magistrates chosen annually at Rome, to govern the commonwealth instead of consuls, with an absolute power to draw up and make laws for the people.

One of the decemvirs had all the ensigns and honours of the function, and the rest had the like in their turn, during the year of their decemvirate. In them was veiled all the legislative authority ever enjoyed by the kings, or, after them, by the consuls. It was the decemviri that drew up the laws of the Twelve Tables, thence called leges decemvirales, which were the whole of the Roman law for a considerable time.