Every day we use words and phrases that we all understand, but are unintelligible to those outside the system. Some, such as abbreviations, have a counterpart in Civ Div, others are of a technical nature. A number have been absorbed into the general language of all Brits, like 'char' and 'chat.' The origins are sometimes clear, many of the older words were nicked from other languages, the 'cuds' for example. But where does 'stag' come from ?