A map, plan or plat of any subdivision or land development, drawn to scale and showing lot and street lines has been approved by the Board of Supervisors of Logan Township in accordance with the terms and provisions of Township Ordinance No. 5-17-79, entitled the "Logan Township Subdivision and Land Development Ordinance." [Chapter 22] The term "subdivision" as used herein shall mean the division or redivision of a lot, tract or parcel of land by any means into two or more lots, tracts, parcels or other divisions of land including changes in existing lot lines for the purpose, whether immediate or future, of lease, partition by the court for distribution to heirs or devisees, transfer of ownership or building or lot development; provided, however, that the subdivision by lease of land for agricultural purposes into parcels of more than 10 acres, not involving any new street or easement of access or any residential dwelling, shall be exempted.