Flächeninhalt
... German for Area (externer Link)
Area means: The amount of space inside a shape or a two-dimensional figure, measured in square units. A rectangle with length 10 cm and width 4 cm has a "Flächeninhalt" of 40 square centimetres. "Flächeninhalt" is often abbreviated to "Fläche" where there is no danger of misunderstanding.