This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
淏 combines 氵 (water) with 昊, which likely contributes sound. The exact historical development is uncertain.
The water radical 氵 beside 昊 suggests something related to water, but the meaning is unclear. Picture a vast, bright expanse of water under the sun.
For コウ, imagine a wide, calm lake reflecting the sun: the sound of a gentle 'koh' echoes across the water, cueing コウ.
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