box, box or enclosure radical (no. 31)
囗 represents a box or enclosure, and it is primarily used as a radical in other characters to convey the idea of surrounding or containing.
囗 is a pictograph of an enclosure or surrounding wall. The modern form retains the simple box shape.
The shape 囗 looks like a box or a fenced enclosure. Imagine a square container that holds things inside.
For イ, picture an easel (イーゼル) shaped like a box: easel -> イ, and the box encloses the canvas.
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