A waist bag, fanny pack, belt bag, moon bag, belly bag (American English), or bumbag (British English) is a small fabric pouch worn like a belt around the waist by use of a strap above the hips that is secured usually with some sort of buckle.
In the 1950s, the British trademarked the term “bum-bag” to reference the pouch that skiers would wear on the slopes. The United States soon coined a sportier alternative: the iconic “fanny pack.”
Some people still call them fanny packs. The accessory, which refers to a bag you can wear around your waist, is now also called a belt bag, waist bag, bum bag and hip bag.
Once the (ahem) butt of many jokes, fanny packs—also known as hip packs, sling bags, crossbody bags, or bum bags—have made a major comeback in recent years. They're now a fully accepted and celebrated wardrobe staple, and with good reason: These compact, hands-free bags are pretty darn useful. Plus, they're cute.
What is the difference between a fanny pack and a bum bag? The truth is there really is no difference (it's the same bag). But the material it's made of (leather or canvas) or the number of pockets it contains can differ some. The intended use is the same - carry what you need and keep your hands free.
Waist bags, bum bags, hip packs, slings, or crossbody bags. Whatever you call them, these bags are back and a must-have for travelers. Like a purse, a fanny pack carries all the small stuff you need for a day of sightseeing like your keys, external battery, and lip balm.