Part of the common elements that is used by
a) the owners of one or more designed units, but not all the owners, in the case of a corporation that is not a common elements condominium.
b) the owners of one or more common interests in the case of common elements condominium.
Source
http://www.search.e-laws.gov.on.ca/en/isysquery/18ccfde3-3103-4f50-a0f4-e9f2d99087ed/3/doc/?search=browseStatutes&context=#hit1