| Term: | Polygon |
| Definition: | Polygons are closed, multi-sided, roughly equidimensional Patterned Ground features, bounded by more or less straight sides; some of the sides may be irregular. Macro-scale Polygons, typically 15 to 30 m across, result from thermal contraction cracking of the ground and form random or oriented Polygonal patterns. They occur in both mineral terrain and peatland. Ice Wedge Polygons are common in poorly drained areas and may be either high-centred or low-centred. |