A lot is a building plot
Actually, it is a building plot, and that is a piece of land of a certain form, and that is usually surrounded by a recognizable boundary (a hedge, a ditch, roads, etc.). The owner of a building plot can then have himself built a house on the ground (provided that all rules etc. Satisfied is of course). RTL has a program ' from Lot to Castle ' where you get an insight into how the processes run (you start with a piece of land, a lot, and in the end you have your dream house).