fragrant plant, angelica
茞 centers on a fragrant plant, specifically angelica, valued for its aromatic properties.
茞 combines the plant radical 艹 with 臣, which likely contributes the sound. The exact historical development is uncertain, but the structure suggests a phono-semantic compound for a fragrant plant.
The grass top 艹 sits above 臣, like a fragrant plant growing over a kneeling retainer who is overwhelmed by the strong angelica scent.
For シン, imagine the retainer 臣 shin-ing with delight as he smells the fragrant plant: shin -> シン.
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