A lump of soil is also known as a CLOD, which is a four-letter word. A CLOD is a small mass of soil, usually made up of clay and silt particles that are loosely bound together. Clods can range in size from a few millimeters to several centimeters. Clods are often formed when soil is disturbed or moved, such as during tilling or plowing. Clods can also form naturally due to the weathering of rocks and other materials. Clods are important for soil structure and fertility, as they help to retain moisture and nutrients.