Big Apple, the
noun Informal.
New York City.
Origin of Big Apple, the
1925–30; promulgated as a tourist slogan during the 1970s; perhaps reuse of earlier “the Apple” (New York City in jazz musicians' argot) with
Big as in
big cheese,
big time, etc.
British Dictionary definitions for big apple
Big Apple
noun
the Big Apple informal
New York City
Word Origin for Big Apple
C20: probably from US jazzmen's earlier use to mean any big, esp northern, city; of obscure origin