A pinafore /ˈpɪnəfɔːr/ (colloquially a pinny /ˈpɪni/ in British English) is a sleeveless garment worn as an apron.
A pinafore is a full apron with two holes for the arms that is tied or buttoned in the back, usually just below the neck.
Further confusion results from some foreign languages, which, unlike English, do not have a distinctive term for the pinafore.
Schürze means "apron" and thus Kinderschürze is used to describe a child's apron or pinafore (in contrast to the German word "Kittelschürze", which refers to an adult garment, typically worn by older women for housework tasks and cleaning).
In 19th century England the pinafore was considered an appropriate garment for girls but on reaching womanhood they were expected to wear aprons.