sunlight, used in personal name
昀 centers on sunlight, specifically the warm light of the sun. It is a rare character used mainly in personal names.
昀 combines 日 (sun) with 匀, which likely contributes the sound. The character is used to express sunlight.
The sun 日 on the left shines evenly over the right part 匀, like sunlight spreading uniformly. Picture a bright, even glow.
For イン, imagine the sun 日 shining into an inn, filling the room with warm sunlight: inn -> イン.
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