WDY was an AM radio station located in Roselle Park, New Jersey, that was licensed to the Radio Corporation of America (RCA) from September 19, 1921 to February 20, 1923, although its broadcasting career only spanned the period from December 15, 1921 through February 17, 1922. Despite being short-lived, WDY was the first broadcasting station licensed in the state of New Jersey, and one of the first in the United States. It also marked RCA's entrance into the broadcasting field, which the company would dominate in the U.S. for the next half century.