arrowhead, weight attached to an arrow by a cord
碆 centers on a specialized archery tool: a weighted arrowhead or a cord-attached weight used to alter an arrow's flight.
碆 combines 石 (stone) with 波 (wave), likely referring to a stone weight that creates a wave-like motion when attached to an arrow cord. The exact historical development is uncertain.
A stone 石 under a wave-like shape 波: imagine a stone weight tied to an arrow, making it fly in a wave-like arc.
For ハ, picture the arrowhead laughing 'Ha!' as it hits the target: Ha -> ハ.
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