Overview
"The Big Apple" is a nickname for New York City. It was first popularized in the 1920s by John J. Fitz Gerald, a sportswriter for the New York Morning Telegraph. Its popularity since the 1970s is due in part to a promotional campaign by the New York tourist authorities.
Origin
Although the history of Big Apple was once thought a mystery, a clearer picture of the term's history has emerged due to the work of historian Barry Popik, and Gerald Cohen of the Missouri University of Science and Technology. A number of false theories had previously existed, including a claim that the term derived from a woman named Eve who ran a brothel in the city. This was subsequently exposed as a hoax.
The earliest known usage of "big apple" appears in the book The Wayfarer in New York (1909), in which Edward Sandford Martin writes: Kansas is apt to see in New York a greedy city ... It inclines to think that the big apple gets a disproportionate share of the national sap. William Safire considered this the coinage, but because the phrase is not quoted in the text, it is likely that it was used as a metaphor, and not as a nickname for the city.
Horse racing origin
The Big Apple was popularized as a name for New York City by John J. Fitz Gerald in a number of horse-racing articles for the New York Morning Telegraph in the 1920s. The earliest of these was a casual reference on 3 May 1921:
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