TREAD DOWN is an action that involves two separate steps. The first step is to OPPRESS, which is defined as to keep down by severe and unjust use of force or authority. The second step is to PAVE, which is defined as to cover with a hard, smooth surface, such as a road or sidewalk. Together, these two steps create the action of TREAD DOWN, which is to press down firmly and evenly with a heavy object, such as a roller, in order to make a surface even and compact.