The just over knee-length trousers that had been worn since the early 17th century. In the 18th century, they had buttoned slits on the side and were buckled at the hem. During the first half of the century, the stockings were pulled over them; later the hem of the culotte covered the top of the stockings.
Culottes were worn by the nobility and gentry; common folk wore ankle-length trousers. Therefore, the term is best known by the derivative sansculottes = "those without culottes", i.e. the common folk who led the French Revolution.