It was used after 1898. In 1903, an early nickname of the "Yankees" baseball team was the "Greater New Yorks."
Today, "Greater New York" usually means the metropolitan area of New York, New Jersey, and Connecticut.
1887:
Seth's Brother's Wife: A Study of Life in Greater New York
by Harold Frederic
12 April 1891, New York Times, pg. 4:
GREATER NEW-YORK.
That was a very pointed letter which Mr. GEORGE WILLIAM CURTIS wrote to the promoters of the project for extending the area of New-York City.