How Well Do You Know English Slang?
1851, named for U.S. feminist reformer Amelia Jenks Bloomer (1818-1894), who promoted them. The surname is attested from c.1200, said to mean literally "iron-worker," from Old English bloma (see bloom (n.2)).
lower part of a "rational dress" for women advocated by Amelia Jenks Bloomer (q.v.) in 1850. The entire costume consisted of a short jacket, a skirt extending below the knee, and the bloomers, or loose "Turkish" trousers, gathered at the ankles.