This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
蕽 combines the grass radical 艹 with 農, but the exact historical development and original meaning are uncertain.
With 艹 (grass) on top and 農 (farming) below, picture a rare, overgrown plant that farmers can't identify—its meaning is as unclear as the plant itself.
For ドウ, imagine a farmer saying 'Doh!' (like Homer Simpson) when he sees this strange weed in his field: Doh -> ドウ.
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