More useless knowledge I picked of in my day working for the company.
Wale, or a wale, is, as I found out, the technical name for the texture of corduroy fabric. The little ridges are called "wales", not to be confused with the Country. So the "Shoosh-shoosh" locomotive sound you make whilst walking in a pair of corduroy overalls is your wales rubbing together.
And now you know.