This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 蕯 is uncertain. It visually combines 艹 (grass) with 隆, but the original purpose and component relationship are unclear.
With no clear meaning, picture a rare plant (艹) growing tall and prosperous (隆) in a hidden garden, but its true nature remains a mystery.
For ロウ, imagine a low-growing plant (艹) that prospers (隆) in a row: low -> ロウ, though the kanji's meaning is uncertain.
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