The latest theory on how New York was called the Big Apple is that horse-racing trainers and jockeys in the 1920s used the term to refer to New York City.
Back then New York had racetracks which offered winners large purses, in other words, a big treat, or a “big apple.”
The nickname was first popularized in the 1920s by John J. Fitz Gerald, a sports writer for the New York Morning Telegraph.
Within its official city limits, New York City has a population of 7.4 million, which is more people than in 39 of the 50 states.