small boat
艑 centers on a small boat, a compact watercraft for travel or transport.
艑 combines 舟 (boat) with 扁, which likely contributes the sound. The exact historical development is uncertain.
A boat 舟 beside 扁, a shape suggesting something flat and compact, like a small, flat-bottomed boat.
For ヘン, imagine a hen sitting in a tiny boat: hen -> ヘン, and the small boat rocks gently.
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