Old Men(perferably over 50) engaged in sexual activity dressed up as Old Lady's
I was totally into that old lady till I found out she was a granny tranny
by Surg May 31, 2006
A transmission with a low gear (granny gear), usually used on trucks and other towing vehicles, to make it easy to take off on a hill with a heavy load.
This truck has a granny tranny so it's easy to learn how to drive stick shift with it.
by Eaglescout1984 January 14, 2009
When your nan gets a cock sewed on to her.
Man, your nan has a big bulge! does she use a cushion for her fanny pad? No, she has no fanny, she's a granny-tranny!
by Bill the Fish August 13, 2006