knife, standing sword radical (no. 18)
刂 is a radical form representing a knife or standing sword, used as a component in other characters. Its standalone meaning is simply 'knife' or the radical itself.
刂 is a radical form derived from 刀 (knife), used as a right-side component in characters. Its shape is a stylized representation of a knife or sword.
The two vertical strokes with a hook look like a simple knife blade. Picture a small standing knife ready to cut.
For トウ, imagine a knife with a sharp point like a toe: toe -> トウ. The knife's tip is as pointed as a toe.
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