The Chinese word 原理 (yuánlǐ), meaning "principle" or "fundamental theory", is a compound formed through the combination of two meaningful characters: 原 (yuán), which carries the sense of "origin", "source", or "original", and 理 (lǐ), which denotes "reason", "logic", or "inner pattern". Together, they create a conceptual synergy where 原 provides the foundational aspect of being primary or fundamental, and 理 contributes the notion of an underlying order or rationale. Thus, the compound semantically signifies the "original reason" or the "fundamental logic" that forms the basis of a system, natural law, or scientific theory, effectively capturing the idea of a core, explanatory principle.