to draw a bamboo bow or cross-bow
箐 centers on the action of drawing a bamboo bow or crossbow, combining the material (bamboo) with the act of pulling back the string.
箐 combines 竹 (bamboo) with 青, which likely contributes a phonetic element. The character refers to a bamboo bow or crossbow, reflecting the material and the action of drawing it.
The top 竹 is bamboo, and the bottom 青 suggests a clear, taut line. Picture a bamboo bow being drawn back until the string is straight and clear.
For セイ, imagine saying 'say' as you draw the bowstring back: 'say' -> セイ, and the bow is ready to shoot.
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