n. In anc. Rom. arch., a barrier, as any construction of boards, osiers, grating, or other light work, placed between the columns of a portico; a light wall occupying the lower part of an intercolumniation; a balustrade or parapet crowning a building or a part of a building; also, a shelf fixed to the wall; the headboard of a bed.n. In ane. Rom. milit. engin.: Boards or planks placed on the fortifications of a camp, or on movable towers or other military engines, to form a kind of roof or shed for the protection of the soldiersn. A movable gallery on wheels, shaped like an arch-covered wagon, in which a besieging party made their approaches.n. In zoology, a larval stage of the echinopædia of certain echinoderms, as a holothurian, ophiurian, or echinid.