large square net, lowered and raised from the bank of the river
罾 centers on a specific type of large, square fishing net that is lowered into and raised from the water, typically operated from the riverbank.
罾 combines 罒 (net) with 曾, which likely contributes a phonetic element. The character specifically denotes a large square net used in fishing.
The top 罒 is a net, and the bottom 曾 looks like a layered structure. Imagine a layered, square net being lowered from a riverbank to catch fish.
For ソウ, picture the net being sewn (ソウ) together from large square pieces: sew -> ソウ, and the net is ready to be lowered into the river.
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