嵌

Mountain radical at the top — the indexing radical, pictograph of three peaks. The classical sense of 嵌 was 'a deep mountain hollow,' a recess cut into a rock face. From that came the modern verb 'to inlay, to set into a hollow' — exactly how a jeweller fits a stone into the carved-out socket of a setting. Same radical caps 岩 (cliff), 岭 (ridge), 峰 (peak).

Lower-left 甘 — sweet, pictograph of a mouth with a dot of food held on the tongue. Pure semantic contribution in this fused right side: it pairs with 欠 to form an old phonetic 欠+甘 stack used in 嵌's traditional reading. Contributes the rounded, held-in-place sense that fits something nestled into a hollow.

Lower-right 欠 supplies the sound qiàn directly — a person bent forward with an open mouth, originally 'to yawn.' Same phonetic feeds 歉 (apology), 钦 (admire). Together with 甘 above it forms the right-hand stack of 嵌, riding the mountain radical above to give 'a deep nesting hollow set in a mountain.'