squared timber, angle, edge, sharp place
棱 centers on a sharp, defined boundary: the edge or angle of a piece of squared timber, or any sharp place. The meanings all point to a clear, angular line or corner.
棱 combines 木 (tree/wood) with 夌, which likely contributes the sound and carries a sense of rising or angularity. Together they suggest the sharp edges of worked timber.
A tree (木) is cut into squared timber, and the right side 夌 looks like a series of sharp angles and edges. Picture a freshly sawn beam with crisp, sharp corners.
For ロウ, imagine a row of squared timbers lined up with sharp edges: row -> ロウ, and each timber has a distinct angle.
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