Eshay means: A member of an Australian youth subculture favouring sportswear and electronic dance music, and commonly associated with criminal activity.. It is mainly Australian English and may not be understood outside that context. There is no real cause for parental concern; it is descriptive vocabulary rather than risky behaviour. It is sporting vocabulary and harmless in itself. 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.