APOTEICHISMUS, in the ancient military art, a kind of line of circumvallation drawn round a place in order to besiege it. The first thing the ancients went about, when they designed to lay close siege to a place, was the Apoteichismus; which sometimes consisted of a double wall, or rampart, raised of earth; the innermost to prevent sudden sallies from the town, the outermost to keep off foreign enemies from coming to the relief of the besieged. This answered to what is called lines of contravallation and circumvallation among the moderns.