sparkling water
洸 centers on water that glitters or sparkles with reflected light, like sunlight dancing on a rippling surface.
洸 combines the water radical 氵 with 光 (light), suggesting water that reflects light and sparkles.
Water 氵 plus light 光: imagine a lake surface catching sunlight and sparkling like countless tiny mirrors.
For コウ, picture a sparkling koi pond: koi -> コウ, and the water glitters with light.
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