Word Origin and History for Knickerbocker
"descendant of Dutch settlers of New York," 1831, from Diedrich Knickerbocker, the name under which Washington Irving published his popular "History of New York" (1809). The pen-name was borrowed from Irving's friend Herman Knickerbocker, and literally means "toy marble-baker."
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knickerbockers (1859), said to be so called for their resemblance to the trousers of old-time Dutchmen in Cruikshank's illustrations for Washington Irving's "History of New York"
Example: His stockings were short, and did not come up to his knickerbockers.
knickers, 1866, shortening of knickerbockers
undergarment now but not originally so.
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FROM KNICKERBOCKERS TO KNICKERS
When men wore loose trousers for sport they were sometimes called knickerbockers. However women's underwear were soon called knickerbockers too. In the late 19th century the word was shortened to knickers. In the USA women's underwear are called panties, which is obviously a diminutive of pants.
At the beginning of the 1800s women still wore a long nightie-like garment under their dress but it was now called a chemise not a shift. However after about 1800 they also wore drawers. Sometimes they came to below the knee or sometimes they were longer garments with frills at the bottom called pantalettes. However by the 1830s only girls not women wore pantalettes.
Today we still say a pair of knickers or panties. That is because in the early 19th century women's underwear consisted to two separate legs joined at the waist. They really were a 'pair'.
At first women's drawers were usually very plain but in the late 19th century they were decorated with lace and bands. In the Winter women often wore woolen knickers and woolen vests.
Victorian women's underwear were sometimes called bloomers. Elizabeth Miller invented loose trousers to be worn by women. The idea was promoted by Amelia Bloomer from 1849 and they became known as bloomers. In time long underwear became known as bloomers.
By the late 19th century in Britain men's underwear were called pants. Men also wore vests. Some men wore combinations, pants and vest in one garment.
Life in the 19th Century
20th Century Underwear
In the 19th century women's underwear was usually open between the legs but in the 20th century closed knickers replaced them.
In the 19th century knickers came down to well below the knee. In the 1920s they became shorter. They ended above the knee. By the 1940s and 1950s many women wore briefs. Men's underwear also became shorter. The word drawers went out of use and they became known as underpants or pants.
http://www.localhistories.org/underwear.html