Accy mode means: Accy mode is the mental and behavioural state you enter when you're deep in accumulator building - obsessively researching form tables, injury lists, and head-to-head records, stacking legs with. 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.