luxuriant, flourishing, used for various plants
葳 centers on lush, vigorous growth, especially of plants. It describes something flourishing or luxuriant, and is used in plant names to convey that thriving quality.
葳 combines the grass radical 艹 with 威, which likely provides the sound. The character is used for plant names and the idea of luxuriance, but the exact historical development is uncertain.
The grass radical 艹 sits above 威, which suggests imposing strength. Picture a field of grass growing so thick and tall that it looks powerful and majestic—truly flourishing.
For イ, imagine a lush garden where every plant is an 'E' (the letter E) shape, standing tall and thriving: E -> イ, and the whole scene is luxuriant.
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