This paper proposes a new physical interpretation of time as the fourth dimension. Rather than treating time as a static geometric axis alongside the three spatial dimensions — as in Einstein’s relativity — we propose that time emerges dynamically from the rotational and orbital motion of three-dimensional space. We demonstrate consistency between this framework and key results of special and general relativity, including the Lorentz factor, E = mc², the Schwarzschild radius, and the weak-field limit of Einstein’s field equations, while offering physical mechanisms that Einstein’s geometric framework leaves unexplained. We situate this proposal within the tradition of relational theories of time, distinguish it from existing approaches, and propose a novel testable prediction: that intrinsic rotation contributes independently to time dilation beyond what current theory accounts for, measurable with existing atomic clock technology. The core ideas in this paper were first developed by L. Guo in a personal document dated February 3, 2024.