The Chinese word **皮疹 (pízhěn)**, meaning "skin rash," is a straightforward **compound noun** formed by combining two meaningful characters: **皮 (pí)**, which means "skin," and **疹 (zhěn)**, which specifically means "rash" or "eruption." It follows a common **modifier-head structure** in Chinese morphology, where the first character **皮** acts as a semantic modifier specifying the location (skin), and the second character **疹** functions as the core head noun indicating the condition itself. Thus, the compound literally and logically translates to "skin-rash," creating a precise medical or descriptive term through direct semantic combination.