lotus
蓉 centers on the lotus flower, especially its blossom. It is used in names and poetic contexts for the lotus.
蓉 combines 艹 (grass/plant) with 容, which likely contributes the sound. Together they specifically denote the lotus flower.
The grass crown 艹 sits above 容, like a lotus blossom rising above the water's surface. Think of the lotus flower emerging from the plant.
For ヨウ, imagine a beautiful lotus floating on a calm pond, and you say 'Yo!' in admiration: Yo -> ヨウ, as you greet the lovely lotus.
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