Adriper means: Someone who is consistently, effortlessly, and almost aggressively well-dressed - not the person who occasionally has a fire fit, but the one whose entire existence seems to be an ongoing fashion. 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.