To bang a girl so hard so fast so many times, that she can barely walk straight, hence, "walking like an old granny".
I fucked courtney granny style, she could barely even stand up the next morning.
by -= RUCKER =- April 26, 2004
1 more definition
Bending her over so far that her hip pops out of place and then she can't move so you may continue to rawdog
I did Gertrude Grannystyle
by LilNykil November 03, 2010