The term **碧眼 (bì yǎn)**, meaning "blue/green eyes," is a classical Chinese compound word formed through a straightforward descriptive structure common in the language. It combines the morpheme **碧 (bì)**, meaning "green" or "bluish-green" (often used for jade or clear skies), with **眼 (yǎn)**, meaning "eye." Together, they create a noun phrase where the first element modifies the second—literally "green/blue eye." This type of formation is a standard **modifier-head** or **attributive** construction in Chinese, similar to "red hair" (红发). Historically, the term was used in classical texts and historical records to describe the physical appearance of people from non-Han ethnicities or regions, notably those of Central Asian or European descent, thus encapsulating a distinct phenotypic trait within a concise, two-character lexical unit.