The crossword solution for the term SEPARATE LEVEL is LAYER. A LAYER is a thin, flat sheet or stratum of material, such as rock, soil, or snow, that is distinct from other surrounding materials. It can also refer to a level or division in a system, such as a LAYER of the atmosphere or a LAYER of the Earth's crust. In computing, a LAYER is a set of software services that provide a platform for applications to run on.