bright
睆 centers on visual brightness: something that appears bright or clear to the eye.
睆 combines 目 (eye) with 完, which likely contributes the sound and may suggest completeness or fullness, together expressing the idea of brightness perceived by the eye. The exact historical development is uncertain.
The eye 目 sees something complete 完 and whole, making it appear bright and clear.
For カン, imagine a bright can of light shining into your eye: can -> カン, and the brightness fills your vision.
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