This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
畈 combines 田 (field) and 反, but the exact historical development and original meaning are uncertain. It may have been a phono-semantic compound, but the details are unclear.
With 田 (field) and 反 (oppose), imagine a field that opposes cultivation—perhaps a stubborn, barren plot. Without a clear meaning, treat it as a field that resists definition.
For ハン, picture a half-cultivated field: half -> ハン, and the field 田 resists full planting.
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