I found out the word meaning from a girl I met in Bar from Ireland. I use to carry my stuff in small fanny pack so my wallet,keys,knife would not fall out of my pockets when skateboarding.
I said "Let me get some money out of my fanny pack." She started laughing and tell me you really should call it a bum pack and the meaning of the word fanny In Ireland,Scotland,England.
Different countries have different name like in Australia when you get drunk you get Pi$$ed.