name of mountain
崋 is a rare kanji used specifically as the name of a mountain. Its standalone meaning is limited to that proper-noun sense.
崋 combines 山 (mountain) with a lower component that likely contributed sound. The exact historical development is uncertain.
The mountain 山 sits on top, marking this as a mountain name. Picture a specific peak labeled with the rest of the character as its nameplate.
For カ, imagine a car parked at the base of this mountain: car -> カ, and the mountain's name starts with that sound.
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