Thin mud is a type of sedimentary material composed of a mixture of clay, SILT, and water. It is often found in riverbeds, lakes, and other bodies of water. The term 'thin mud' can also be used to describe a type of soil that is composed of a mixture of clay and SILT particles. The crossword solutions for the term 'thin mud' are 'SLIME' (5 letters) and 'SILT' (4 letters). SLIME is a type of viscous, slippery substance that is composed of water and a variety of organic and inorganic compounds. SILT is a type of sedimentary material composed of very small particles of rock and mineral fragments.