1. In the commonly used Udden–Wentworth scale, particles between 4μ‎m and 62.57 μ‎m in size. Other classifications exist. In pedology, silt refers to mineral soil particles that range in diameter from 0.02 to 0.002 μ‎m in the international system, or from 0.05 to 0.002 μ‎m in the USDA system. See particle size.

2. A class of soil texture.