layer, storey, floor

層 is composed of the radical 尸 (corpse) and 曾 (once). 尸 is a pictograph of a person sitting with knees bent, extending to represent dwelling places or buildings; 曾 is a pictograph of a steamer pot, carrying the sense of layering or stacking. Thus, 層 originally referred to multi-storied buildings or structures stacked upward, later extending to denote layers, tiers, strata, or levels.