A lot shown on the original plan of an original survey. A lot, block, part or other unit of land shown on a plan registered or deposited under the Registry Act or Land Titles Act.
Source
http://www.search.e-laws.gov.on.ca/en/isysquery/18ccfde3-3103-4f50-a0f4-e9f2d99087ed/6/doc/?search=browseStatutes&context=#hit1