gorge
嶰 centers on a deep, narrow valley between mountains: a gorge. The meaning is tied to a specific geographical feature rather than a broad concept.
嶰 combines 山 (mountain) with 解, which likely contributes a phonetic role. The exact historical development is uncertain, but the structure suggests a mountain-related word with the sound カイ or ケ.
The left side 山 means mountain, and the right side 解 suggests splitting or unraveling. Picture a mountain split apart by a deep gorge, like a crack unraveling the rock.
For カイ, imagine a kayak (カイ) navigating through a narrow mountain gorge: kayak -> カイ, and the gorge walls tower on both sides.