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A <b>fanny pack</b> (known as a <b>bum bag</b> in the UK) is a small fabric pouch usually secured with a zipper and worn by use of a strap usually around the hips or waist. One style trend involves wearing the pack across the chest.

The word 'fanny' is American slang for a person's [[ass|buttocks]]. The word 'bum' means the same thing in Britain and many Commonwealth countries.
fanny pack