fanny packfanny pack
a small, usually zippered purse or pouch worn at the waist, for carrying keys, a wallet, etc.
Origin of fanny pack; from fanny: so called because often worn at the back of the waist
A waist pack, especially as worn with the pouch over the buttocks.
(plural fanny packs)
While fanny is acceptable in Canada and the US, the term can be offensive in other countries.