arrow with attached silk cord
矰 refers to a specialized arrow with a silk cord attached, used for retrieval or tethering. The meaning is narrow and concrete, centered on this specific hunting or military tool.
矰 combines 矢 (arrow) with 曾, which likely contributes the sound. The character is a phono-semantic compound for a specific type of arrow.
The left side 矢 is an arrow, and the right side 曾 looks like a spool or container. Picture an arrow with a silk cord wound around a spool, ready to be shot and retrieved.
For ソウ, imagine the arrow's cord making a soft 'sow' sound as it unspools through the air: sow -> ソウ.
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