"LOT" shall mean a parcel of land, of any size or shape, occupied by one principal building or devoted to one principal use and containing the permitted accessory buildings and uses customarily incidental to such principal building or use, and including such open spaces as are required under the provisions of these Regulations. Where land is undeveloped "lot" shall mean all contiguous land owned by the same owner or owners except subdivision lots owned by a person not required to obtain reapproval of the subdivision pursuant to 2.17 of the Newtown Land Subdivision Regulations effective October 1967. The mere recording or filing of a map in the Town Clerk's Office shall not constitute the creation of a lot.