form of female undergarment/panties whereby the rear fabric is replaced with spaghetti string to reduce visible panty lines, and give the impression under a skirt or dress that the female is not wearing panties at all. Recently worn as bikini bottoms as exterior clothing. So named because tension on the spaghetti strap seems to be in a position to stimulate the female Graffenberg spot, aka G-spot. <-edit: that is total humbug. the g-spot is inside the vagina, on the abdominal side, about a few cm inside. It would make sense when talking about stimulating the clitoris (besides the G-spot is supposed to be a part of it), but that way it would be a C-String.
Sure, the G string on that girl shows off her ass, but look over here...gotta love a girl with guts enough to wear granny panties out to the beach.