"valid mode" means: A temporary state of being fully switched on, genuine, and operating with integrity — the version of yourself that doesn't cut corners or pe.... This is a fairly neutral word with no inherent risk attached. There is no real cause for parental concern; it is descriptive vocabulary rather than something dangerous. If your child uses it, context will usually make the meaning clear. A brief, curious question about where they heard it is generally enough to know whether to follow up.