mountain cave
峇 centers on a mountain cave: a natural hollow or cavern within a mountain.
峇 combines 山 (mountain) and 合 (join, fit), likely suggesting a hollow where parts of the mountain meet or fit together to form a cave. The exact historical development is uncertain.
The mountain 山 on top and the joining 合 below suggest a place where the mountain's parts come together to form a cave.
For コウ, imagine a mountain cave echoing with a deep 'koh' sound: koh -> コウ, the sound of the cave.
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