Shoes
Barleycorn
The unit behind US and UK shoe sizes: one third of an inch.
US and UK shoe sizes go up by one barleycorn, or 1/3 inch (about 8.5 mm), per full size, and half a barleycorn per half size.
US and UK sizes use the same step but start counting from different points, which is why the same shoe has a different number in each system.
Related terms
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