The term “fly” in the context of pants originates from the Old English word “flowan,” meaning to flow. It refers to the piece of fabric that covers the zipper, not the zipper itself. The term gained popularity in the 19th century when tailors began using it to describe a flap of cloth attached at one end to cover an opening in a garment. This usage was particularly noted for its association with the right side of men’s trousers, distinguishing it from women’s garments, which may have different openings