bright, pure
晧 centers on light and clarity: something bright and pure, like the sun's radiance. The two given meanings are closely linked, with purity being a natural extension of brightness.
晧 combines 日 (sun) with 告, which likely contributes the sound. The character expresses brightness or purity associated with sunlight.
The sun 日 on the left shines on the right side 告, making everything bright and pure. Imagine the sun's rays cleansing and illuminating.
For コウ, picture a bright, pure coat of sunlight: coat -> コウ, and the sun 日 makes it shine.
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