Pressure in excess of atmospheric pressure is called what?

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Gauge pressure is the pressure above atmospheric pressure. The atmosphere exerts a baseline pressure on everything, so any pressure in excess of that ambient value is read by a typical pressure gauge as gauge pressure. Mathematically, gauge pressure equals absolute pressure minus atmospheric pressure. For example, if the absolute pressure is 1200 kPa and the atmospheric pressure is about 101.3 kPa, the gauge pressure is roughly 1098.7 kPa. If the system were below ambient, the gauge pressure would be negative (a vacuum). Absolute pressure is the total pressure relative to zero, which includes atmospheric pressure, while atmospheric pressure is simply the ambient air pressure. Working pressure is not the standard term for this concept. Therefore, the pressure in excess of atmospheric pressure is gauge pressure.