mountain pass
嵶 centers on a mountain pass, specifically a gentle or sloping pass where the terrain is not steep.
嵶 combines 山 (mountain) with 弱 (weak, gentle), suggesting a mountain feature that is not steep or harsh. The exact historical development is uncertain, but the component combination likely points to a gentle mountain pass.
A mountain 山 with a weak 弱 slope: imagine a mountain pass so gentle that even a weak hiker can cross it easily.
For たお, picture a gentle mountain pass where the trail is so easy you can just 'tao' (like 'dow' in 'endow') along without effort: tao -> たお.
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