river in Henan province, flowing
瀼 centers on flowing water, specifically as a river name in Henan province. The core idea is a body of water in motion.
瀼 combines 氵 (water) with 襄, which likely contributes the sound. The character is used as a proper name for a river in Henan, and its structure suggests a phono-semantic origin.
The water radical 氵 beside 襄 suggests a specific river. Picture the flowing water of the 瀼 river in Henan, with the right side representing the sound of its name.
For ジョウ, imagine a gentle flowing river where you can hear the sound 'joh' as the water moves: 'joh' -> ジョウ, like the soft flow of the 瀼 river.
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