Although in many cases lots are smaller than plots which are smaller than parcels, there is no uniformity of use and, as will be seen from the unece reference below on land administration terms, all these variations of terms are defined as parcels of land. In practice, a register is kept (in UK it is the Land Registry) and the land is defined by reference to a filed plan outlining the dimensions of the property comprised in the title. If the property is subdivided, those subdivisions will likewise be defined by reference to a plan. It may be that this is not helpful for the purposes of your translation but it is what rules on the ground (pardon the pun).

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