The Chinese word 上流 (shàngliú), meaning "upper class" or "high society," is formed through a metaphorical compounding of its two constituent characters: 上 (shàng), meaning "up" or "upper," and 流 (liú), meaning "flow" or "stream." Literally, it translates to "upper stream" or "upstream." This formation draws an analogy from geography, where the upstream section of a river is often seen as the source, being pure, elevated, and originating before the downstream, which becomes mixed and common. By semantic extension, this natural hierarchy is applied to human society, where 上流 metaphorically represents the elite, refined, and prestigious social stratum that is considered superior in status, behavior, and taste, much like the elevated and originating position of a river's source.