眼

The organ of sight; extended to mean a small circular opening, aperture, or eyelet.

Noun. Frequently used in compound nouns to describe the luster or shape of an object via analogy to biological eyes.

Contrast with 目: where the two overlap, 眼 tends to emphasize the physical instrument of sight rather than the faculty of seeing.

In Pre-Qin and early Han texts, 目 is the dominant term. The appearance of 眼 in these earlier strata may indicate a colloquial register or a specific anatomical focus.

When encountered in descriptions of inanimate objects, prioritize "hole" or "opening." In medical or alchemical contexts, the term may refer specifically to the orbit (socket) of the eye or a designated acupuncture point.