gilgai

1. (Australia) A small concavity or depression between ridges, where rainwater gathers.Examples: "Though it wasn′t a heavy storm it was enough to put water in gilgai holes and scatter the horses."; "Argilliturbation is manifested within Vertisol profiles and on the surface as gilgai microtopography, with relief exceeding commonly 15 cm (Fig. 10.35)."; "One of its most remarkable features is its patterns of gilgai. The gilgais are small, almost circular depressions from a few centimetres to as much as 50 cm deep in the plain and several metres across."Synonyms: crab-hole, dead-men's grave, melon holeAustralia