What does Wales mean?
Most commonly used to describe the pile ribs on corduroy fabrics, wales refers to any lengthwise ribs or ridges on woven fabrics.
Heddels explains Wales
Wales refer to the number of ridges or cords per inch on fabric. The lower the wale number for a fabric, the wider the ridges. The standard wale count for corduroy is between 10 and 12 wales per inch.
Up-close shot of wales: