Granny sack is a word that me and a friend created ... it means quite a few things

1. old ball sack (dirty one)
2. old bag (as in old person)
3. a new brand of bin bags specially made for old people (if parents or an elderly person asks)
4. also you can go granny sacking which is getting a beanbag or your ball sack and slapping people in the face with it

5. getting out your old ball sack (dirty one again) when people are taking photos so they have unwanted memories of your old balls :p
i'll do an example for each one

1. john mccririck is a granny sack
2. john mccririck is a granny sack that picks his nose

3. john mccririck just bought some granny sacks for the bins
4.OMG john mccrirck is granny sacking in manchester and he's being arrested ... yeey

5. posh spice looked through her holiday pics from spain and saw that john mccririck was granny sacking in the background
by grannysackerpro October 30, 2011
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Toby: Woah Bruh, Cool Fanny pack!
Baylor: You mean a granny sack?
Sonny: The fuck you talking bout
by GrannySacks4Life July 2, 2015
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