Drawers are generally the antique style of ladies underpants - long legs and baggy around the nether regions. In Victorian times the crotch was usually split at the centre seam to enable women wearing crinolines and hooped skirts to visit the toilet more easily. If you want to know how they did it, check out the weirdly fascinating Youtube video below.
The split crotch went out of fashion towards the end of the 19th century.
Drawers were called drawers because they were drawn up to be put on. Before this time, underpants consisted of two separate legs, put on separately and tied together at the waist.
Drawers are sometimes called bloomers, but bloomers are more correctly an outer garment.