Mud

Mud is loam, silt, or clay mixed with water. Mud is usually formed after rainfall or near water sources. Ancient mud deposits hardened over geological time to form sedimentary rock such as shale or mudstone. When geological deposits of mud are formed in estuaries, the resultant layers are termed bay muds. Mud has also been used for centuries as a construction resource, mostly for houses, and also as a binder. An Old English word for it was fen, now in most dialects referring to a type of wetland.