Douglas Harper's Etymology Dictionary
g spot
also g-spot, 1981, short for Gräfenberg spot, named for German gynecologist Ernst Gräfenberg (1881-1957), who described it in 1950.
Usage examples of "g spot".
On top of a stack of files on her desk, I could see a copy of Cosmo, offering articles on the G spot, cosmetic breast surgery, and social rape.