1) Any New Yorker 2) East Coast hoopster 
Knickerbocker, also spelled Knikkerbakker, Knikkerbacker, and Knickerbacker, is a surname that dates back to the early settlers of New Netherland that was popularized by Washington Irving in 1809 when he published his satirical A History of New York under the pseudonym `Diedrich Knickerbocker`. It was also a term for Manhattan`s aristocracy `i...[Spokane, Washington] Knickerbocker in Spokane, Washington is a Beaux Arts building. It was designed by architect Albert Held and was built in 1911. It was listed on the U.S. National Register of Historic Places in 1987. ...
• (n.) A linsey-woolsey fabric having a rough knotted surface on the right side; used for women`s dresses.
Knick'er·bock`er noun A linsey- woolsey fabric having a rough knotted surface on the right side; used for women's dresses. 
Knickerbocker is American slang for a resident of New York state.
a descendant of the Dutch settlers of New York. · any New Yorker.