sandcastle/ˈsæn(d)ˌkæsəl/EtymologyFrom sand + castle.nounA sculpture made of sand and resembling a miniature castle; typically, but not always, made for fun by a child on a beach.“Children learn the importance of water in soil mechanics from an early age. They learn on the beach while making sandcastles. When they use dry sand, their castle flows into a heap even as they lift the bucket. The particles of sand have no cohesion and little friction between them.”