This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
沜 combines 氵 (water) with 片, but the exact historical development and original meaning are uncertain.
With water 氵 beside a fragment 片, imagine a broken piece of a riverbank or a scattered puddle, but the true meaning is unclear.
For ハン, picture a half-submerged hand (ハン) in the water: hand -> ハン, reaching out from the fragment of a broken shore.
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