zig-zag

1. Romanesque decorative Z- or V- and inverted V-(λ) shaped device (chevron or dancette), either incised or in relief, occurring in a continuous band or string (as at Southwell Minster, Notts.), as an ornament around an arch or series of arches (see order), or cut into the drum of a pier (as at Durham Cathedral). This architectural ornament has several variations

2. Plan-form of fortifications with gun-emplacements built outwards with salient angles.