Condominium

Noun

 * 1) (U.S.) a building in which each unit is owned by an individual but the grounds, structure etc is owned jointly
 * 2) A unit or apartment in such a complex
 * 3) The legal tenure involved
 * 4) Joint sovereignty over a territory
 * 5) Ownership of a property in which each unit owner has an undivided interest in common elements.

Thesaurus
apartment house, association, cochairmanship, complicity, contribution, cooperative apartment house, copartnership, copartnery, cotenancy, duplex, duplex house, engagement, flats, having a part, high-rise apartment building, involvement, joint chairmanship, joint control, joint ownership, joint tenancy, partaking, participation, partnership, sharing, suffrage, tenement, voting