Nonaluminum means: A straightforward North American English compound adjective meaning not made from or pertaining to aluminum. Typically used in manufacturing, engineering, and product specifications to distinguish. It is informal slang, fine in casual speech but not suited to formal contexts. 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.