GROUND DOWN is a term used to describe the process of reducing something to a smaller size or shape. ERODED (6 letters) is a term used to describe the process of wearing away or being worn away by wind, water, or other natural forces. GRATED (6 letters) is a term used to describe the process of reducing something into small pieces or particles by rubbing it against a rough surface. Together, these terms describe the process of reducing something to a smaller size or shape by wearing away or rubbing it against a rough surface.