This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
苭 combines the grass radical 艹 with 幼, but the historical origin and original meaning are uncertain. It may have been a plant name or a variant form, but no clear etymology is established.
The grass radical 艹 sits above 幼 (young). Imagine a young sprout just emerging from the soil, but its purpose is unclear.
For ヨウ, picture a young sprout (幼) growing under the grass (艹), and think of the sound 'yo' as in 'young': yo -> ヨウ.
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