The Chinese word **污秽** is formed through the combination of two semantically similar characters: **污** (wū), which primarily means "dirt," "stain," or "pollution," and **秽** (huì), which means "filth," "unclean," or "impure." This structure follows a common pattern in Chinese lexicon known as a **synonymous compound**, where two characters with closely related meanings are paired to create a single, more emphatic, and often more abstract or comprehensive term. Together, they reinforce each other to denote a state of being morally or physically defiled, dirty, or foul, with the combined meaning being stronger and more nuanced than either character alone.