includes any street, road, thoroughfare, sanitary passage, square or open space shown on a general plan of a township or settlement, filed in any deeds registry or Surveyor-General’s office, and all land (other than erven shown on the general plan) the control whereof is vested, to the entire exclusion of the owner, in a local authority or to which the owners of erven in the township have a common right, and for purposes of this definition "settlement" means a group of pieces of land or of subdivisions of a piece of land which are used or intended for use mainly for farming or horticulture, and includes a combination of such groups which is suitable for inclusion in one property register;