璧

A phono-semantic compound composed of:

玉 — semantic component meaning “jade; precious stone”; 辟 — phonetic component indicating the sound (벽 / bì). The character originally denoted a ritual jade disk, used in ancient China for ceremonies and symbolic purposes.
Semantic development: - circular jade disk with a hole; - precious jade; - symbol of perfection or completeness; - metaphor (e.g., the moon).

완벽 (完璧) — perfection; completeness (literally “complete jade disk”)

벽옥 (璧玉) — fine jade

In ancient China, 璧 was a ritual object symbolizing heaven and purity.

The proportions distinguish similar jade forms:

璧 — hole smaller than the outer ring;

環 — hole ≈ ring width;

瑗 — hole larger than the ring.

The expression 完璧 reflects the idea of a flawless, perfectly formed jade disk.