an aboriginal word used by whitemen in the neighbourhood of Bourke, New South Wales, to denotea saucer-shaped depression in the ground which forms a naturalreservoir for rainwater. Ghilgais vary from 20 to 100yards in diameter, and are from five to ten feet deep. Theydiffer from Claypans (q.v.), in being more regular inoutline and deeper towards the centre, whereas Claypansare generally flat-bottomed. Their formation is probably dueto subsidence.