Hip pack means: Another name for a fanny pack or bum bag (British English) - the small zippered pouch worn on a belt around the waist or hips. 'Hip pack' is arguably the most anatomically accurate of the three. There is no real cause for parental concern; it is descriptive vocabulary rather than risky behaviour. If your teen uses it, context will usually make the intent clear. A short, curious question about where they heard it is usually all that is needed to know whether to follow up.