What is a "gymslip"?

A gymslip is a type of school uniform worn by girls, typically consisting of a sleeveless pinafore-style dress worn over a blouse or sweater. It is usually knee-length and made of a sturdy material such as wool or polyester. The gymslip was originally designed for physical education classes but later became a common school uniform item for girls in the United Kingdom and other countries. Some modern variations of the gymslip have incorporated a pleated skirt or a more modern design, but the basic style remains the same.