Adiabatic walls are walls of the building shell that separate heated spaces. They are called adiabatic due to the absence of heat transfer through them. A typical example is a fire wall separating row-houses or other adjacent buildings.
Without modelling the zones of the adjacent building area correction helps you to take into account the effect of that building.
The structures of the building next to the other are categorised as external. You should eliminate it by reducing the area of these structures to 0 m².
In addition the amount of area with what the external structure was reduced with, has to be added to the internal structure.
Please note that also the Slab on grade structure must be modified according to the changed internal/external structure ratio.
In this way you can take into account the thermal effect of any adjacent building in Energy Calculation.