curved, bent, curved wall enclosure
闉 centers on a curved or bent shape, specifically a curved wall enclosure. The core idea is something that is not straight but arched or rounded, often in the context of a surrounding barrier.
闉 combines 門 (gate) with 垔, which likely contributes the sound and the idea of something curved or bent, as in a curved wall. The exact historical development is uncertain.
Picture a gate 門 that is not straight but curved, like an arched entrance. Inside, the component 垔 looks like a bent wall made of earth 土 and a curved top, reinforcing the idea of a curved enclosure.
For イン, imagine an inn with a curved, arched gateway: inn -> イン, and the curved wall enclosure welcomes you inside.
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